Move roles/matrix* to roles/custom/matrix*

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.

roles/custom/matrix-bridge-hookshot/templates/registration.yml.j2

@@ -0,0 +1,30 @@
+#jinja2: lstrip_blocks: "True"
+id: matrix-hookshot # This can be anything, but must be unique within your homeserver
+as_token: {{ matrix_hookshot_appservice_token|to_json }} # This again can be a random string
+hs_token: {{ matrix_hookshot_homeserver_token|to_json }} # ..as can this
+namespaces:
+  rooms: []
+  users:
+{% if matrix_hookshot_github_enabled %}
+    - regex: "@_github_.*:{{ matrix_domain }}"
+      exclusive: true
+{% endif %}
+{% if matrix_hookshot_gitlab_enabled %}
+    - regex: "@_gitlab_.*:{{ matrix_domain }}" # Where foobar is your homeserver's domain
+      exclusive: true
+{% endif %}
+{% if matrix_hookshot_jira_enabled %}
+    - regex: "@_jira_.*:{{ matrix_domain }}" # Where foobar is your homeserver's domain
+      exclusive: true
+{% endif %}
+{% if matrix_hookshot_generic_enabled %}
+    - regex: "@{{ matrix_hookshot_generic_user_id_prefix }}.*:{{ matrix_domain }}" # Where foobar is your homeserver's domain // depending on userIdPrefix setting in conf
+      exclusive: true
+{% endif %}
+  aliases:
+    - regex: "#github_.+:{{ matrix_domain }}"
+      exclusive: true
+
+sender_localpart: hookshot
+url: "http://{{ matrix_hookshot_container_url }}:{{ matrix_hookshot_appservice_port }}" # This should match the bridge.port in your config file
+rate_limited: false