Continuation of 54a281a425.
Related to #188 (Github Pull Request).

Facebook API token not required

Validate_config was copied from the telegram bridge code, but doesn't
apply to the facebook bridge.

Fix ansible deprecations

Refers to #89 (Github Issue)

While using certbot means we'll have both files retrieved,
it's actually the fullchain.pem file that we use in nginx configuration.

Using that one for the check makes more sense.

Fixes #155 (Github Issue)

Move bridges into separate roles

Add a variable to control the stop tasks

Reasoning is the same as for matrix-org/synapse#5023.

For us, the journal used to contain `docker` for all services, which
is not very helpful when looking at them all together (`journalctl -f`).

Fix case of the mxisd ldap.connection.baseDNs option in matrix_mxisd_configuration_extension_yaml comment

Provide a sample rest_auth_endpoint close to actual setup

Fix matrix_synapse_ext_password_provider_ldap_start_tls (it's boolean)

The goal is to move each bridge into its own separate role.
This commit starts off the work on this with 2 bridges:
- mautrix-telegram
- mautrix-whatsapp

Each bridge's role (including these 2) is meant to:

- depend only on the matrix-base role

- integrate nicely with the matrix-synapse role (if available)

- integrate nicely with the matrix-nginx-proxy role (if available and if
required). mautrix-telegram bridge benefits from integrating with
it.

- not break if matrix-synapse or matrix-nginx-proxy are not used at all

This has been provoked by #174 (Github Issue).

Add a task to stop services (and remove containers)

Move around options on updating-users-passwords.md

and provide an example for using the admin API

Mention the Synapse User Admin API on updating-users-passwords.md

The bit about the matrix-make-user-admin script was messed up (it wasn't actually a code block so the "<username>" was hidden). For me at least it seems like the ``` syntax is much harder to accidentally mess up.

Bump postgres versions