Official support ends today (2021-11-11).
Synapse still supports v9.6, but we'd better force users to transition
to newer versions anyway.

Until now, we were leaving services "enabled"
(symlinks in /etc/systemd/system/multi-user.target.wants/).

We clean these up now. Broken symlinks may still exist in older
installations that enabled/disabled services. We're not taking care
to fix these up. It's just a cosmetic defect anyway.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1377

Regresion since https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1139

We were applying the low-memory system patch to webpack.config.js
on systems with < 4GB memory.

From now on, we also let people force-enable patching by toggling the
`matrix_client_element_container_image_self_build_low_memory_system_patch_enabled`
variable.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1357

docker-ce does not like quotes around the shm-size value

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1268

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1364

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1362

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1357

Should have been done in 63f5a88fa0.

https://github.com/matrix-org/matrix-appservice-irc/releases/tag/0.32.1

https://github.com/vector-im/element-web/releases/tag/v1.9.3

In short, the problem is that older Postgres versions store passwords
hashed as md5. When you dump such a database, the dump naturally also
contains md5-hashed passwords.
Restoring from that dump used to create users and updates their passwords
with these md5 hashes.
However, Postgres v14 prefers does not like md5-hashed passwords now (by default),
which breaks connectivity. Postgres v14 prefers `scram-sha-256` for
authentication.

Our solution is to just ignore setting passwords (`ALTER ROLE ..`
statements) when restoring dumps. We don't need to set passwords as
defined in the dump anyway, because the playbook creates users
and manages their passwords by itself.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1340

https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1311#issuecomment-945718866

From the [Synapse 1.43.0 release highlights](https://matrix.org/blog/2021/09/21/synapse-1-43-0-released):
> Asks clients to prefer [room version 9](https://github.com/matrix-org/matrix-doc/pull/3375) when creating restricted rooms ([#10772](https://github.com/matrix-org/synapse/issues/10772)), via the API defined in [MSC3244: room version capabilities](https://github.com/matrix-org/matrix-doc/pull/3244).

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1322

I am not using this bridge and haven't tested this but multiple people have said 1.5.0 isn't working and 1.8.0 works for them so it seems to make sense to update.

https://github.com/matrix-org/matrix-appservice-slack/issues/618#issuecomment-929849093