Allow Jitsi XMPP webscoket support for users using own webserver.

Added:
 - Conditional localhost Port bindings for Jitsi Prosody systemd template
- Added variable to main.yml to allow overriding from vars.yml

roles/matrix-jitsi/defaults/main.yml

@@ -175,7 +175,7 @@ matrix_jitsi_prosody_container_extra_arguments: []
 
 # List of systemd services that matrix-jitsi-prosody.service depends on
 matrix_jitsi_prosody_systemd_required_services_list: ['docker.service']
-
+matrix_jitsi_prosody_container_http_host_bind_port: ''
 
 matrix_jitsi_jicofo_docker_image: "{{ matrix_container_global_registry_prefix }}jitsi/jicofo:{{ matrix_jitsi_container_image_tag }}"
 matrix_jitsi_jicofo_docker_image_force_pull: "{{ matrix_jitsi_jicofo_docker_image.endswith(':latest') }}"

roles/matrix-jitsi/templates/prosody/matrix-jitsi-prosody.service.j2

@@ -16,6 +16,9 @@ ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }}
 ExecStart={{ matrix_host_command_docker }} run --rm --name matrix-jitsi-prosody \
 			--log-driver=none \
 			--network={{ matrix_docker_network }} \
+			{% if matrix_jitsi_prosody_container_http_host_bind_port %}
+			-p {{ matrix_jitsi_prosody_container_http_host_bind_port }}:{{ matrix_jitsi_prosody_container_http_host_bind_port }}
+			{% endif %}
 			--env-file={{ matrix_jitsi_prosody_base_path }}/env \
 			--mount type=bind,src={{ matrix_jitsi_prosody_config_path }},dst=/config \
 			--mount type=bind,src={{ matrix_jitsi_prosody_plugins_path }},dst=/prosody-plugins-custom \