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-nginx-proxy/templates/systemd/matrix-nginx-proxy.service.j2

@@ -0,0 +1,65 @@
+#jinja2: lstrip_blocks: "True"
+[Unit]
+Description=Matrix nginx-proxy server
+{% for service in matrix_nginx_proxy_systemd_required_services_list %}
+Requires={{ service }}
+After={{ service }}
+{% endfor %}
+{% for service in matrix_nginx_proxy_systemd_wanted_services_list %}
+Wants={{ service }}
+{% endfor %}
+DefaultDependencies=no
+
+[Service]
+Type=simple
+Environment="HOME={{ matrix_systemd_unit_home_path }}"
+ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} kill matrix-nginx-proxy 2>/dev/null || true'
+ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} rm matrix-nginx-proxy 2>/dev/null || true'
+
+ExecStart={{ matrix_host_command_docker }} run --rm --name matrix-nginx-proxy \
+			--log-driver=none \
+			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
+			--cap-drop=ALL \
+			--read-only \
+			--tmpfs=/tmp:rw,noexec,nosuid,size={{ matrix_nginx_proxy_tmp_directory_size_mb }}m \
+			{% if matrix_nginx_proxy_synapse_cache_enabled %}
+			--tmpfs=/tmp/synapse-cache:rw,noexec,nosuid,size={{ matrix_nginx_proxy_tmp_cache_directory_size_mb }}m\
+			{% endif %}
+			--network={{ matrix_docker_network }} \
+			{% if matrix_nginx_proxy_container_http_host_bind_port %}
+			-p {{ matrix_nginx_proxy_container_http_host_bind_port }}:8080 \
+			{% endif %}
+			{% if matrix_nginx_proxy_https_enabled and matrix_nginx_proxy_container_https_host_bind_port %}
+			-p {{ matrix_nginx_proxy_container_https_host_bind_port }}:8443 \
+			{% endif %}
+			{% if matrix_nginx_proxy_proxy_matrix_federation_api_enabled and matrix_nginx_proxy_container_federation_host_bind_port %}
+			-p {{ matrix_nginx_proxy_container_federation_host_bind_port }}:{{ matrix_nginx_proxy_proxy_matrix_federation_port }} \
+			{% endif %}
+			--mount type=bind,src={{ matrix_nginx_proxy_base_path }}/nginx.conf,dst=/etc/nginx/nginx.conf,ro \
+			--mount type=bind,src={{ matrix_nginx_proxy_data_path }},dst={{ matrix_nginx_proxy_data_path_in_container }},ro \
+			--mount type=bind,src={{ matrix_nginx_proxy_confd_path }},dst=/etc/nginx/conf.d,ro \
+			{% if matrix_ssl_retrieval_method != 'none' %}
+			--mount type=bind,src={{ matrix_ssl_config_dir_path }},dst={{ matrix_ssl_config_dir_path }},ro \
+			{% endif %}
+			--mount type=bind,src={{ matrix_static_files_base_path }},dst={{ matrix_static_files_base_path }},ro \
+			{% for volume in matrix_nginx_proxy_container_additional_volumes %}
+			-v {{ volume.src }}:{{ volume.dst }}:{{ volume.options }} \
+			{% endfor %}
+			{% for arg in matrix_nginx_proxy_container_extra_arguments %}
+			{{ arg }} \
+			{% endfor %}
+			{{ matrix_nginx_proxy_docker_image }}
+
+{% for network in matrix_nginx_proxy_container_additional_networks %}
+ExecStartPost={{ matrix_host_command_sh }} -c 'attempt=0; while [ $attempt -le 29 ]; do attempt=$(( $attempt + 1 )); if [ "`docker inspect -f {{ '{{.State.Running}}' }} matrix-nginx-proxy 2> /dev/null`" = "true" ]; then break; fi; sleep 1; done; {{ matrix_host_command_docker }} network connect {{ network }} matrix-nginx-proxy'
+{% endfor %}
+
+ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} kill matrix-nginx-proxy 2>/dev/null || true'
+ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} rm matrix-nginx-proxy 2>/dev/null || true'
+ExecReload={{ matrix_host_command_docker }} exec matrix-nginx-proxy /usr/sbin/nginx -s reload
+Restart=always
+RestartSec=30
+SyslogIdentifier=matrix-nginx-proxy
+
+[Install]
+WantedBy=multi-user.target