The goal is to have a single variable which tells us which homeserver
software is in use. Much simpler than having if/elif/elif checks for
variables like (`matrix_synapse_enabled` and `matrix_dendrite_enabled`, etc.)
everywhere.

This brings dendrite.yaml up to date and cleans things up a bit.

Discussed in https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1514

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1480

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1242

* Copy/update mautrix_facebook group_vars to mautrix_twitter
* Replace facebook -> twitter, fb -> twt, remove presence var
* Enable playbook in setup.yml

This is useful when Synapse is using a worker setup. In that case,
we don't want appservices to connect to `matrix-synapse:8008`, because
not all APIs are exposed there.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1449

Add a self-build option for the Dimension Dockerfile.
 - This helps further support arm64 hosts (i.e. A1.Flex w/Oracle)

This change forces ansible to decrypt the variable with ansible-vault if encrypted, to avoid the error '{"msg": "Unexpected templating type error occurred on ({{ matrix_synapse_macaroon_secret_key | password_hash('sha512') }}): secret must be unicode or bytes, not ansible.parsing.yaml.objects.AnsibleVaultEncryptedUnicode"}'
Every other variable in the playbook was found to have no problems with encryption.
The change has no negative impact on non-encrypted matrix_synapse_macaroon_secret_key.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1397
and https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1399

* fix for string concatenation on matrix_synapse_account_threepid_delegates_email and matrix_synapse_account_threepid_delegates_msisdn

* .editorconfig should not be ignored

* Restore .gitignore

Co-authored-by: b <b@b>
Co-authored-by: Slavi Pantaleev <slavi@devture.com>

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

Also fixes the appservice and homeserver tokens for the Googlechat bridge,
so that they're not the same as the ones for the Hangouts bridge.

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

This bridge doesn't support SQLite anyway, so it's not necessary
to carry around configuration fields and code for migration from SQLite
to Postgres. There's nothing to migrate.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1171

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1145

Supersedes https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1145

This commit introduces a new role that downloads and installs the
prometheus community postgres exporter  https://github.com/prometheus-community/postgres_exporter.
A new credential is added to matrix_postgres_additional_databases that
allows the exporter access to the database to gather statistics.
A new dashboard was added to the grafana role, with some refactoring
to enable the dashboard only if the new role is enabled.
I've included some basic instructions for how to enable the role in
the Docs section.

In terms of testing, I've tested enabling the role, and disabling
it to make sure it cleans up the container and systemd role.