Changes in synapse v0.13.2 (2016-02-11)
=======================================

* Fix bug where ``/events`` would fail to skip some events if there had been
  more events than the limit specified since the last request (PR #570)

Changes in synapse v0.13.3 (2016-02-11)
=======================================

* Fix bug where ``/sync`` would occasionally return events in the wrong room.

Changes in synapse v0.14.0 (2016-03-30)
=======================================

No changes from v0.14.0-rc2

Changes in synapse v0.14.0-rc2 (2016-03-23)
===========================================

Features:

* Add published room list API (PR #657)

Changes:

* Change various caches to consume less memory (PR #656, #658, #660, #662,
  #663, #665)
* Allow rooms to be published without requiring an alias (PR #664)
* Intern common strings in caches to reduce memory footprint (#666)

Bug fixes:

* Fix reject invites over federation (PR #646)
* Fix bug where registration was not idempotent (PR #649)
* Update aliases event after deleting aliases (PR #652)
* Fix unread notification count, which was sometimes wrong (PR #661)

Changes in synapse v0.14.0-rc1 (2016-03-14)
===========================================

Features:

* Add event_id to response to state event PUT (PR #581)
* Allow guest users access to messages in rooms they have joined (PR #587)
* Add config for what state is included in a room invite (PR #598)
* Send the inviter's member event in room invite state (PR #607)
* Add error codes for malformed/bad JSON in /login (PR #608)
* Add support for changing the actions for default rules (PR #609)
* Add environment variable SYNAPSE_CACHE_FACTOR, default it to 0.1 (PR #612)
* Add ability for alias creators to delete aliases (PR #614)
* Add profile information to invites (PR #624)

Changes:

* Enforce user_id exclusivity for AS registrations (PR #572)
* Make adding push rules idempotent (PR #587)
* Improve presence performance (PR #582, #586)
* Change presence semantics for ``last_active_ago`` (PR #582, #586)
* Don't allow ``m.room.create`` to be changed (PR #596)
* Add 800x600 to default list of valid thumbnail sizes (PR #616)
* Always include kicks and bans in full /sync (PR #625)
* Send history visibility on boundary changes (PR #626)
* Register endpoint now returns a refresh_token (PR #637)

Bug fixes:

* Fix bug where we returned incorrect state in /sync (PR #573)
* Always return a JSON object from push rule API (PR #606)
* Fix bug where registering without a user id sometimes failed (PR #610)
* Report size of ExpiringCache in cache size metrics (PR #611)
* Fix rejection of invites to empty rooms (PR #615)
* Fix usage of ``bcrypt`` to not use ``checkpw`` (PR #619)
* Pin ``pysaml2`` dependency (PR #634)
* Fix bug in ``/sync`` where timeline order was incorrect for backfilled events
  (PR #635)

Changes in synapse v0.14.0-rc1 (2016-03-14)
===========================================

Features:

* Add event_id to response to state event PUT (PR #581)
* Allow guest users access to messages in rooms they have joined (PR #587)
* Add config for what state is included in a room invite (PR #598)
* Send the inviter's member event in room invite state (PR #607)
* Add error codes for malformed/bad JSON in /login (PR #608)
* Add support for changing the actions for default rules (PR #609)
* Add environment variable SYNAPSE_CACHE_FACTOR, default it to 0.1 (PR #612)
* Add ability for alias creators to delete aliases (PR #614)
* Add profile information to invites (PR #624)

Changes:

* Enforce user_id exclusivity for AS registrations (PR #572)
* Make adding push rules idempotent (PR #587)
* Improve presence performance (PR #582, #586)
* Change presence semantics for ``last_active_ago`` (PR #582, #586)
* Don't allow ``m.room.create`` to be changed (PR #596)
* Add 800x600 to default list of valid thumbnail sizes (PR #616)
* Always include kicks and bans in full /sync (PR #625)
* Send history visibility on boundary changes (PR #626)
* Register endpoint now returns a refresh_token (PR #637)

Bug fixes:

* Fix bug where we returned incorrect state in /sync (PR #573)
* Always return a JSON object from push rule API (PR #606)
* Fix bug where registering without a user id sometimes failed (PR #610)
* Report size of ExpiringCache in cache size metrics (PR #611)
* Fix rejection of invites to empty rooms (PR #615)
* Fix usage of ``bcrypt`` to not use ``checkpw`` (PR #619)
* Pin ``pysaml2`` dependency (PR #634)
* Fix bug in ``/sync`` where timeline order was incorrect for backfilled events
  (PR #635)

Changes in synapse v0.14.0-rc2 (2016-03-23)
===========================================

Features:

* Add published room list API (PR #657)

Changes:

* Change various caches to consume less memory (PR #656, #658, #660, #662,
  #663, #665)
* Allow rooms to be published without requiring an alias (PR #664)
* Intern common strings in caches to reduce memory footprint (#666)

Bug fixes:

* Fix reject invites over federation (PR #646)
* Fix bug where registration was not idempotent (PR #649)
* Update aliases event after deleting aliases (PR #652)
* Fix unread notification count, which was sometimes wrong (PR #661)

Changes in synapse v0.15.0-rc1 (2016-04-26)
===========================================

Features:

* Add login support for Javascript Web Tokens, thanks to Niklas Riekenbrauck
  (PR #671,#687)
* Add URL previewing support (PR #688)
* Add login support for LDAP, thanks to Christoph Witzany (PR #701)
* Add GET endpoint for pushers (PR #716)

Changes:

* Never notify for member events (PR #667)
* Deduplicate identical ``/sync`` requests (PR #668)
* Require user to have left room to forget room (PR #673)
* Use DNS cache if within TTL (PR #677)
* Let users see their own leave events (PR #699)
* Deduplicate membership changes (PR #700)
* Increase performance of pusher code (PR #705)
* Respond with error status 504 if failed to talk to remote server (PR #731)
* Increase search performance on postgres (PR #745)

Bug fixes:

* Fix bug where disabling all notifications still resulted in push (PR #678)
* Fix bug where users couldn't reject remote invites if remote refused (PR #691)
* Fix bug where synapse attempted to backfill from itself (PR #693)
* Fix bug where profile information was not correctly added when joining remote
  rooms (PR #703)
* Fix bug where register API required incorrect key name for AS registration
  (PR #727)

Changes in synapse v0.16.0 (2016-06-09)
=======================================

NB: As of v0.14 all AS config files must have an ID field.

Bug fixes:

* Don't make rooms published by default (PR #857)

Changes in synapse v0.16.0-rc2 (2016-06-08)
===========================================

Features:

* Add configuration option for tuning GC via ``gc.set_threshold`` (PR #849)

Changes:

* Record metrics about GC (PR #771, #847, #852)
* Add metric counter for number of persisted events (PR #841)

Bug fixes:

* Fix 'From' header in email notifications (PR #843)
* Fix presence where timeouts were not being fired for the first 8h after
  restarts (PR #842)
* Fix bug where synapse sent malformed transactions to AS's when retrying
  transactions (Commits 310197b, 8437906)

Performance Improvements:

* Remove event fetching from DB threads (PR #835)
* Change the way we cache events (PR #836)
* Add events to cache when we persist them (PR #840)

Changes in synapse v0.16.0-rc1 (2016-06-03)
===========================================

Version 0.15 was not released. See v0.15.0-rc1 below for additional changes.

Features:

* Add email notifications for missed messages (PR #759, #786, #799, #810, #815,
  #821)
* Add a ``url_preview_ip_range_whitelist`` config param (PR #760)
* Add /report endpoint (PR #762)
* Add basic ignore user API (PR #763)
* Add an openidish mechanism for proving that you own a given user_id (PR #765)
* Allow clients to specify a server_name to avoid 'No known servers' (PR #794)
* Add secondary_directory_servers option to fetch room list from other servers
  (PR #808, #813)

Changes:

* Report per request metrics for all of the things using request_handler (PR
  #756)
* Correctly handle ``NULL`` password hashes from the database (PR #775)
* Allow receipts for events we haven't seen in the db (PR #784)
* Make synctl read a cache factor from config file (PR #785)
* Increment badge count per missed convo, not per msg (PR #793)
* Special case m.room.third_party_invite event auth to match invites (PR #814)

Bug fixes:

* Fix typo in event_auth servlet path (PR #757)
* Fix password reset (PR #758)

Performance improvements:

* Reduce database inserts when sending transactions (PR #767)
* Queue events by room for persistence (PR #768)
* Add cache to ``get_user_by_id`` (PR #772)
* Add and use ``get_domain_from_id`` (PR #773)
* Use tree cache for ``get_linearized_receipts_for_room`` (PR #779)
* Remove unused indices (PR #782)
* Add caches to ``bulk_get_push_rules*`` (PR #804)
* Cache ``get_event_reference_hashes`` (PR #806)
* Add ``get_users_with_read_receipts_in_room`` cache (PR #809)
* Use state to calculate ``get_users_in_room`` (PR #811)
* Load push rules in storage layer so that they get cached (PR #825)
* Make ``get_joined_hosts_for_room`` use get_users_in_room (PR #828)
* Poke notifier on next reactor tick (PR #829)
* Change CacheMetrics to be quicker (PR #830)

Changes in synapse v0.15.0-rc1 (2016-04-26)
===========================================

Features:

* Add login support for Javascript Web Tokens, thanks to Niklas Riekenbrauck
  (PR #671,#687)
* Add URL previewing support (PR #688)
* Add login support for LDAP, thanks to Christoph Witzany (PR #701)
* Add GET endpoint for pushers (PR #716)

Changes:

* Never notify for member events (PR #667)
* Deduplicate identical ``/sync`` requests (PR #668)
* Require user to have left room to forget room (PR #673)
* Use DNS cache if within TTL (PR #677)
* Let users see their own leave events (PR #699)
* Deduplicate membership changes (PR #700)
* Increase performance of pusher code (PR #705)
* Respond with error status 504 if failed to talk to remote server (PR #731)
* Increase search performance on postgres (PR #745)

Bug fixes:

* Fix bug where disabling all notifications still resulted in push (PR #678)
* Fix bug where users couldn't reject remote invites if remote refused (PR #691)
* Fix bug where synapse attempted to backfill from itself (PR #693)
* Fix bug where profile information was not correctly added when joining remote
  rooms (PR #703)
* Fix bug where register API required incorrect key name for AS registration
  (PR #727)

Changes in synapse v0.16.0-rc1 (2016-06-03)
===========================================

Version 0.15 was not released. See v0.15.0-rc1 below for additional changes.

Features:

* Add email notifications for missed messages (PR #759, #786, #799, #810, #815,
  #821)
* Add a ``url_preview_ip_range_whitelist`` config param (PR #760)
* Add /report endpoint (PR #762)
* Add basic ignore user API (PR #763)
* Add an openidish mechanism for proving that you own a given user_id (PR #765)
* Allow clients to specify a server_name to avoid 'No known servers' (PR #794)
* Add secondary_directory_servers option to fetch room list from other servers
  (PR #808, #813)

Changes:

* Report per request metrics for all of the things using request_handler (PR
  #756)
* Correctly handle ``NULL`` password hashes from the database (PR #775)
* Allow receipts for events we haven't seen in the db (PR #784)
* Make synctl read a cache factor from config file (PR #785)
* Increment badge count per missed convo, not per msg (PR #793)
* Special case m.room.third_party_invite event auth to match invites (PR #814)

Bug fixes:

* Fix typo in event_auth servlet path (PR #757)
* Fix password reset (PR #758)

Performance improvements:

* Reduce database inserts when sending transactions (PR #767)
* Queue events by room for persistence (PR #768)
* Add cache to ``get_user_by_id`` (PR #772)
* Add and use ``get_domain_from_id`` (PR #773)
* Use tree cache for ``get_linearized_receipts_for_room`` (PR #779)
* Remove unused indices (PR #782)
* Add caches to ``bulk_get_push_rules*`` (PR #804)
* Cache ``get_event_reference_hashes`` (PR #806)
* Add ``get_users_with_read_receipts_in_room`` cache (PR #809)
* Use state to calculate ``get_users_in_room`` (PR #811)
* Load push rules in storage layer so that they get cached (PR #825)
* Make ``get_joined_hosts_for_room`` use get_users_in_room (PR #828)
* Poke notifier on next reactor tick (PR #829)
* Change CacheMetrics to be quicker (PR #830)

Changes in synapse v0.16.0-rc2 (2016-06-08)
===========================================

Features:

* Add configuration option for tuning GC via ``gc.set_threshold`` (PR #849)

Changes:

* Record metrics about GC (PR #771, #847, #852)
* Add metric counter for number of persisted events (PR #841)

Bug fixes:

* Fix 'From' header in email notifications (PR #843)
* Fix presence where timeouts were not being fired for the first 8h after
  restarts (PR #842)
* Fix bug where synapse sent malformed transactions to AS's when retrying
  transactions (Commits 310197b, 8437906)

Performance Improvements:

* Remove event fetching from DB threads (PR #835)
* Change the way we cache events (PR #836)
* Add events to cache when we persist them (PR #840)

Changes in synapse v0.16.1 (2016-06-20)
=======================================

Bug fixes:

* Fix assorted bugs in ``/preview_url`` (PR #872)
* Fix TypeError when setting unicode passwords (PR #873)

Performance improvements:

* Turn ``use_frozen_events`` off by default (PR #877)
* Disable responding with canonical json for federation (PR #878)

Changes in synapse v0.16.1-rc1 (2016-06-15)
===========================================

Features: None

Changes:

* Log requester for ``/publicRoom`` endpoints when possible (PR #856)
* 502 on ``/thumbnail`` when can't connect to remote server (PR #862)
* Linearize fetching of gaps on incoming events (PR #871)

Bugs fixes:

* Fix bug where rooms where marked as published by default (PR #857)
* Fix bug where joining room with an event with invalid sender (PR #868)
* Fix bug where backfilled events were sent down sync streams (PR #869)
* Fix bug where outgoing connections could wedge indefinitely, causing push
  notifications to be unreliable (PR #870)

Performance improvements:

* Improve ``/publicRooms`` performance(PR #859)

Changes in synapse v0.16.1-r1 (2016-07-08)
==========================================

THIS IS A CRITICAL SECURITY UPDATE.

This fixes a bug which allowed users' accounts to be accessed by unauthorised
users.

Changes in synapse v0.16.1-rc1 (2016-06-15)
===========================================

Features: None

Changes:

* Log requester for ``/publicRoom`` endpoints when possible (PR #856)
* 502 on ``/thumbnail`` when can't connect to remote server (PR #862)
* Linearize fetching of gaps on incoming events (PR #871)

Bugs fixes:

* Fix bug where rooms where marked as published by default (PR #857)
* Fix bug where joining room with an event with invalid sender (PR #868)
* Fix bug where backfilled events were sent down sync streams (PR #869)
* Fix bug where outgoing connections could wedge indefinitely, causing push
  notifications to be unreliable (PR #870)

Performance improvements:

* Improve ``/publicRooms`` performance(PR #859)

Changes in synapse v0.17.0 (2016-08-08)
=======================================

This release contains significant security bug fixes regarding authenticating
events received over federation. PLEASE UPGRADE.

This release changes the LDAP configuration format in a backwards incompatible
way, see PR #843 for details.

Changes:

* Add federation /version API (PR #990)
* Make psutil dependency optional (PR #992)

Bug fixes:

* Fix URL preview API to exclude HTML comments in description (PR #988)
* Fix error handling of remote joins (PR #991)

Changes in synapse v0.17.0-rc4 (2016-08-05)
===========================================

Changes:

* Change the way we summarize URLs when previewing (PR #973)
* Add new ``/state_ids/`` federation API (PR #979)
* Speed up processing of ``/state/`` response (PR #986)

Bug fixes:

* Fix event persistence when event has already been partially persisted
  (PR #975, #983, #985)
* Fix port script to also copy across backfilled events (PR #982)

Changes in synapse v0.17.0-rc3 (2016-08-02)
===========================================

Changes:

* Forbid non-ASes from registering users whose names begin with '_' (PR #958)
* Add some basic admin API docs (PR #963)

Bug fixes:

* Send the correct host header when fetching keys (PR #941)
* Fix joining a room that has missing auth events (PR #964)
* Fix various push bugs (PR #966, #970)
* Fix adding emails on registration (PR #968)

Changes in synapse v0.17.0-rc2 (2016-08-02)
===========================================

(This release did not include the changes advertised and was identical to RC1)

Changes in synapse v0.17.0-rc1 (2016-07-28)
===========================================

This release changes the LDAP configuration format in a backwards incompatible
way, see PR #843 for details.

Features:

* Add purge_media_cache admin API (PR #902)
* Add deactivate account admin API (PR #903)
* Add optional pepper to password hashing (PR #907, #910 by KentShikama)
* Add an admin option to shared secret registration (breaks backwards compat)
  (PR #909)
* Add purge local room history API (PR #911, #923, #924)
* Add requestToken endpoints (PR #915)
* Add an /account/deactivate endpoint (PR #921)
* Add filter param to /messages. Add 'contains_url' to filter. (PR #922)
* Add device_id support to /login (PR #929)
* Add device_id support to /v2/register flow. (PR #937, #942)
* Add GET /devices endpoint (PR #939, #944)
* Add GET /device/{deviceId} (PR #943)
* Add update and delete APIs for devices (PR #949)

Changes:

* Rewrite LDAP Authentication against ldap3 (PR #843 by mweinelt)
* Linearize some federation endpoints based on (origin, room_id) (PR #879)
* Remove the legacy v0 content upload API. (PR #888)
* Use similar naming we use in email notifs for push (PR #894)
* Optionally include password hash in createUser endpoint (PR #905 by
  KentShikama)
* Use a query that postgresql optimises better for get_events_around (PR #906)
* Fall back to 'username' if 'user' is not given for appservice registration.
  (PR #927 by Half-Shot)
* Add metrics for psutil derived memory usage (PR #936)
* Record device_id in client_ips (PR #938)
* Send the correct host header when fetching keys (PR #941)
* Log the hostname the reCAPTCHA was completed on (PR #946)
* Make the device id on e2e key upload optional (PR #956)
* Add r0.2.0 to the "supported versions" list (PR #960)
* Don't include name of room for invites in push (PR #961)

Bug fixes:

* Fix substitution failure in mail template (PR #887)
* Put most recent 20 messages in email notif (PR #892)
* Ensure that the guest user is in the database when upgrading accounts
  (PR #914)
* Fix various edge cases in auth handling (PR #919)
* Fix 500 ISE when sending alias event without a state_key (PR #925)
* Fix bug where we stored rejections in the state_group, persist all
  rejections (PR #948)
* Fix lack of check of if the user is banned when handling 3pid invites
  (PR #952)
* Fix a couple of bugs in the transaction and keyring code (PR #954, #955)

Changes in synapse v0.17.0-rc1 (2016-07-28)
===========================================

This release changes the LDAP configuration format in a backwards incompatible
way, see PR #843 for details.

This release contains significant security bug fixes regarding authenticating
events received over federation. Please upgrade.

Features:

* Add purge_media_cache admin API (PR #902)
* Add deactivate account admin API (PR #903)
* Add optional pepper to password hashing (PR #907, #910 by KentShikama)
* Add an admin option to shared secret registration (breaks backwards compat)
  (PR #909)
* Add purge local room history API (PR #911, #923, #924)
* Add requestToken endpoints (PR #915)
* Add an /account/deactivate endpoint (PR #921)
* Add filter param to /messages. Add 'contains_url' to filter. (PR #922)
* Add device_id support to /login (PR #929)
* Add device_id support to /v2/register flow. (PR #937, #942)
* Add GET /devices endpoint (PR #939, #944)
* Add GET /device/{deviceId} (PR #943)
* Add update and delete APIs for devices (PR #949)

Changes:

* Rewrite LDAP Authentication against ldap3 (PR #843 by mweinelt)
* Linearize some federation endpoints based on (origin, room_id) (PR #879)
* Remove the legacy v0 content upload API. (PR #888)
* Use similar naming we use in email notifs for push (PR #894)
* Optionally include password hash in createUser endpoint (PR #905 by
  KentShikama)
* Use a query that postgresql optimises better for get_events_around (PR #906)
* Fall back to 'username' if 'user' is not given for appservice registration.
  (PR #927 by Half-Shot)
* Add metrics for psutil derived memory usage (PR #936)
* Record device_id in client_ips (PR #938)
* Send the correct host header when fetching keys (PR #941)
* Log the hostname the reCAPTCHA was completed on (PR #946)
* Make the device id on e2e key upload optional (PR #956)
* Add r0.2.0 to the "supported versions" list (PR #960)
* Don't include name of room for invites in push (PR #961)

Bug fixes:

* Fix substitution failure in mail template (PR #887)
* Put most recent 20 messages in email notif (PR #892)
* Ensure that the guest user is in the database when upgrading accounts
  (PR #914)
* Fix various edge cases in auth handling (PR #919)
* Fix 500 ISE when sending alias event without a state_key (PR #925)
* Fix bug where we stored rejections in the state_group, persist all
  rejections (PR #948)
* Fix lack of check of if the user is banned when handling 3pid invites
  (PR #952)
* Fix a couple of bugs in the transaction and keyring code (PR #954, #955)

Changes in synapse v0.17.0-rc2 (2016-08-02)
===========================================

Changes:

* Forbid non-ASes from registering users whose names begin with '_' (PR #958)
* Add some basic admin API docs (PR #963)

Bug fixes:

* Send the correct host header when fetching keys (PR #941)
* Fix joining a room that has missing auth events (PR #964)
* Fix various push bugs (PR #966, #970)
* Fix adding emails on registration (PR #968)

Changes in synapse v0.17.0-rc3 (2016-08-02)
===========================================

Changes:

* Forbid non-ASes from registering users whose names begin with '_' (PR #958)
* Add some basic admin API docs (PR #963)

Bug fixes:

* Send the correct host header when fetching keys (PR #941)
* Fix joining a room that has missing auth events (PR #964)
* Fix various push bugs (PR #966, #970)
* Fix adding emails on registration (PR #968)

Changes in synapse v0.17.0-rc4 (2016-08-05)
===========================================

Changes:

* Change the way we summarize URLs when previewing (PR #973)
* Add new ``/state_ids/`` federation API (PR #979)
* Speed up processing of ``/state/`` response (PR #986)

Bug fixes:

* Fix event persistence when event has already been partially persisted
  (PR #975, #983, #985)
* Fix port script to also copy across backfilled events (PR #982)

Changes in synapse v0.17.1 (2016-08-24)
=======================================

Changes:

* Delete old received_transactions rows (PR #1038)
* Pass through user-supplied content in /join/$room_id (PR #1039)

Bug fixes:

* Fix bug with backfill (PR #1040)

Changes in synapse v0.17.1-rc1 (2016-08-22)
===========================================

Features:

* Add notification API (PR #1028)

Changes:

* Don't print stack traces when failing to get remote keys (PR #996)
* Various federation /event/ perf improvements (PR #998)
* Only process one local membership event per room at a time (PR #1005)
* Move default display name push rule (PR #1011, #1023)
* Fix up preview URL API. Add tests. (PR #1015)
* Set ``Content-Security-Policy`` on media repo (PR #1021)
* Make notify_interested_services faster (PR #1022)
* Add usage stats to prometheus monitoring (PR #1037)

Bug fixes:

* Fix token login (PR #993)
* Fix CAS login (PR #994, #995)
* Fix /sync to not clobber status_msg (PR #997)
* Fix redacted state events to include prev_content (PR #1003)
* Fix some bugs in the auth/ldap handler (PR #1007)
* Fix backfill request to limit URI length, so that remotes don't reject the
  requests due to path length limits (PR #1012)
* Fix AS push code to not send duplicate events (PR #1025)

Changes in synapse v0.17.1-rc1 (2016-08-22)
===========================================

Features:

* Add notification API (PR #1028)

Changes:

* Don't print stack traces when failing to get remote keys (PR #996)
* Various federation /event/ perf improvements (PR #998)
* Only process one local membership event per room at a time (PR #1005)
* Move default display name push rule (PR #1011, #1023)
* Fix up preview URL API. Add tests. (PR #1015)
* Set ``Content-Security-Policy`` on media repo (PR #1021)
* Make notify_interested_services faster (PR #1022)
* Add usage stats to prometheus monitoring (PR #1037)

Bug fixes:

* Fix token login (PR #993)
* Fix CAS login (PR #994, #995)
* Fix /sync to not clobber status_msg (PR #997)
* Fix redacted state events to include prev_content (PR #1003)
* Fix some bugs in the auth/ldap handler (PR #1007)
* Fix backfill request to limit URI length, so that remotes don't reject the
  requests due to path length limits (PR #1012)
* Fix AS push code to not send duplicate events (PR #1025)

Changes in synapse v0.17.2 (2016-09-08)
=======================================

This release contains security bug fixes. Please upgrade.

No changes since v0.17.2

Changes in synapse v0.17.2-rc1 (2016-09-05)
===========================================

Features:

* Start adding store-and-forward direct-to-device messaging (PR #1046, #1050,
  #1062, #1066)

Changes:

* Avoid pulling the full state of a room out so often (PR #1047, #1049, #1063,
  #1068)
* Don't notify for online to online presence transitions. (PR #1054)
* Occasionally persist unpersisted presence updates (PR #1055)
* Allow application services to have an optional 'url' (PR #1056)
* Clean up old sent transactions from DB (PR #1059)

Bug fixes:

* Fix None check in backfill (PR #1043)
* Fix membership changes to be idempotent (PR #1067)
* Fix bug in get_pdu where it would sometimes return events with incorrect
  signature