Fix remote invite rejections not coming down sync

remove trailing ,

This was broken in PR #4405, commit 886e5acc, where we changed remote
rejections to be outliers.

The fix is to explicitly add the leave event in when we know its an out
of band invite. We can't always add the event as if the server is/was in
the room there might be more events to send down the sync than just the
leave.

Server capabilities support

* Fix replication for room v3

We were not correctly quoting the path fragments over http replication,
which meant that it exploded when the event IDs had a slash in them

* Newsfile

* Handle listening for ACME requests on IPv6 addresses

the weird url-but-not-actually-a-url-string doesn't handle IPv6 addresses
without extra quoting. Building a string which you are about to parse again
seems like a weird choice. Let's just use listenTCP, which is consistent with
what we do elsewhere.

* Clean up the default ACME config

make it look a bit more consistent with everything else, and tweak the defaults
to listen on port 80.

* newsfile

Fix bug where synapse fails to start if no_tls set

Tiny .well-known fixes

Merge branch 'neilj/room_capabilities' of github.com:matrix-org/synapse into neilj/room_capabilities

Implement workaround for login error.

Signed-off-by: Robert Jacob <xperimental@solidproject.de>

Enable support for room version 3

Implement rechecking of redactions for room versions v3

Remove usages of event ID's domain