Add support for controlling Matrix federation

roles/matrix-server/templates/synapse/homeserver.yaml.j2

@@ -119,12 +119,16 @@ use_presence: {{ matrix_synapse_use_presence|to_json }}
 #  - lon.example.com
 #  - nyc.example.com
 #  - syd.example.com
+{% if matrix_synapse_federation_domain_whitelist is not none %}
+federation_domain_whitelist: {{ matrix_synapse_federation_domain_whitelist|to_json }}
+{% endif %}
 
 # List of ports that Synapse should listen on, their purpose and their
 # configuration.
 listeners:
   # Main HTTPS listener
   # For when matrix traffic is sent directly to synapse.
+  {% if matrix_synapse_federation_enabled %}
   -
     # The port to listen for HTTPS requests on.
     port: 8448
@@ -157,6 +161,7 @@ listeners:
     #   "/_matrix/my/custom/endpoint":
     #     module: my_module.CustomRequestHandler
     #     config: {}
+  {% endif %}
 
   # Unsecure HTTP listener,
   # For when matrix traffic passes through loadbalancer that unwraps TLS.