Use JSON when querying the IS's /store-invite endpoint

FederationDeniedError is a subclass of SynapseError, which is a subclass of
CodeMessageException, so if e is a FederationDeniedError, then this check for
FederationDeniedError will never be reached since it will be caught by the
check for CodeMessageException above.  The check for CodeMessageException does
almost the same thing as this check (since FederationDeniedError initialises
with code=403 and msg="Federation denied with %s."), so may as well just keep
allowing it to handle this case.

When asking for the relations of an event, include the original event in the response. This will mostly be used for efficiently showing edit history, but could be useful in other circumstances.

Allow newly-registered users to lookup their own profiles

Nothing uses this now, so we can remove the dead code, and clean up the
API.

Since we're changing the shape of the return value anyway, we take the
opportunity to give the method a better name.

When a user creates an account and the 'require_auth_for_profile_requests' config flag is set, and a client that performed the registration wants to lookup the newly-created profile, the request will be denied because the user doesn't share a room with themselves yet.

Fixes https://github.com/matrix-org/synapse/issues/2306

It was pretty unclear what was going on, so I've added a couple of log lines.

* Update ModuleApi to avoid register(generate_token=True)

This is the only place this is still used, so I'm trying to kill it off.

* changelog

* Factor out some redundant code in the login impl

Also fixes a redundant access_token which was generated during jwt login.

* changelog

This is only used in tests, so...

* Add a few more common environment directory names to black exclusion

* Add changelog

This adds a default push rule following the proposal in
[MSC2153](https://github.com/matrix-org/matrix-doc/pull/2153).

See also https://github.com/vector-im/riot-web/issues/10208
See also https://github.com/matrix-org/matrix-js-sdk/pull/976

Riot team would like some extra fields as part of m.replace, so here you go.

Fixes: #5598

This has never been documented, and I'm not sure it's ever been used outside
sytest.

It's quite a lot of poorly-maintained code, so I'd like to get rid of it.

For now I haven't removed the database table; I suggest we leave that for a
future clearout.

this hasn't done anything for years

- Put the default window_size back to 1000ms (broken by #5181)
- Make the `rc_federation` config actually do something
- fix an off-by-one error in the 'concurrent' limit
- Avoid creating an unused `_PerHostRatelimiter` object for every single
  incoming request

The runtime errors that dealt with local email password resets talked about config options that users may not even have in their config file yet (if upgrading). Instead, the cryptic errors are now replaced with hopefully much more helpful ones.

* Improve the backwards compatibility re-exports of synapse.logging.context.

* reexport logformatter too

* Add a sytest blacklist file

* Add changelog

* Add blacklist to manifest

Suggest people use a config file for Docker instead of env vars

* Fix 'utime went backwards' errors on daemonization.

Fixes #5608

* remove spurious debug

Fixes #5602, #5603

Removes any `SMTP_*` docker container environment variables from having any effect on the default config.

Fixes https://github.com/matrix-org/synapse/issues/5430