Atomically persist events when joining a room over federation/

Validate the receipt type before passing it on to the receipt handler

Set m.room.canonical_alias on room creation.

Remove some of the unused definitions from synapse

Allow config file path to be configurable in in synctl

Also, allow it to be run from directories other than the synapse directory

Fix order of ON constraints in _get_rooms_for_user_where_membership

Fix bug where we sometimes didn't fetch all the keys requested for a server.

Change default history visibility for private rooms