Implemented draft for top domain as matrix identifier name

roles/docker-matrix-compose/templates/synapse/homeserver.yaml.j2

@@ -1,4 +1,4 @@
-server_name: "{{domain_matrix_synapse}}"
+server_name: "{{top_domain}}"
 pid_file: /data/homeserver.pid
 listeners:
   - port: 8008

roles/docker-matrix-compose/templates/well-known.j2

@@ -0,0 +1,3 @@
+{
+    "m.server": "{{synapse_domain}}:443"
+}