Make Docker image listen on ipv6 as well as ipv4

Signed-off-by: Cédric Laudrel <dek@iono.me>

Currently when fetching state groups from the data store we make two
hits two the database: once for members and once for non-members (unless
request is filtered to one or the other). This adds needless load to the
datbase, so this PR refactors the lookup to make only a single database
hit.

Add config option to control alias creation

fix race condiftion in calling initialise_reserved_users

Autocreate autojoin rooms

there's really no point spinning up two separate jobs for these.

I don't think we ever use this, and it slows things down. If we want to use it,
we should just do so on a couple of builds rather than all of them.

(We really don't need to kick off 10 builds for the branch as well as 10 for
the PR)

Co-Authored-By: neilisfragile <neil@matrix.org>

Co-Authored-By: neilisfragile <neil@matrix.org>

Allow backslashes in event field filters

Fix a number of flake8 errors