Related to 0241c71a4c

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3270#issuecomment-2143782962

With this change, it should be possible for people to adjust the Docker
dependency from `docker.service` to something else (e.g. `pkg-ContainerManager-dockerd.service`),
or to completely eliminate it by setting `devture_systemd_docker_base_docker_service_name` to an empty string.

This makes it easier for people to use the playbook against a Synology DSM server.

All homeserver implementations have been updated to support this as
well.

It's just Jitsi that possibly doesn't work with anything other than `auth-secret`.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3191

Not that it seems necessary right now, but it makes it consistent with
all other roles.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/2592

.. and try to auto-switch between `bind` and `volume` depending on
whether there's a slash in the `src` path.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/2482

This helps large deployments which need to open up thousands of ports
(matrix_coturn_turn_udp_min_port, matrix_coturn_turn_udp_min_port)

On a test VM, opening 1k ports takes 17 seconds for Docker to "publish"
all of these ports (setting up forwarding rules with the firewall, etc),
so service startup and shutdown take a long amount of time.

If host-networking is used, there's no need to open any ports at all
and startup/shutdown can be quick.

Inspired by: https://www.rtcsec.com/article/cve-2020-26262-bypass-of-coturns-access-control-protection/

Part of a security hardening provoked by:
https://www.rtcsec.com/article/cve-2020-26262-bypass-of-coturns-access-control-protection/

This paves the way for installing other roles into `roles/galaxy` using `ansible-galaxy`,
similar to how it's done in:

- https://github.com/spantaleev/gitea-docker-ansible-deploy
- https://github.com/spantaleev/nextcloud-docker-ansible-deploy

In the near future, we'll be removing a lot of the shared role code from here
and using upstream roles for it. Some of the core `matrix-*` roles have
already been extracted out into other reusable roles:

- https://github.com/devture/com.devture.ansible.role.postgres
- https://github.com/devture/com.devture.ansible.role.systemd_docker_base
- https://github.com/devture/com.devture.ansible.role.timesync
- https://github.com/devture/com.devture.ansible.role.vars_preserver
- https://github.com/devture/com.devture.ansible.role.playbook_runtime_messages
- https://github.com/devture/com.devture.ansible.role.playbook_help

We just need to migrate to those.