Get the configuration template to generate a clean configuration.

The templates is still pretty complex, but at least the configuration
file that get generated is well formed.

templates/rabbitmq.config.j2

@@ -1,11 +1,20 @@
 [
   {rabbit, [
-    {% if rabbitmq_conf_tcp_listeners_address != '' %}
-    {tcp_listeners, [{"{{ rabbitmq_conf_tcp_listeners_address }}", {{ rabbitmq_conf_tcp_listeners_port }}}]}{% if rabbitmq_ssl %},{% endif %}
-    {% else %}
-    {tcp_listeners, []}{% if rabbitmq_ssl %},{% endif %}
-    {% endif %}
-    {% if rabbitmq_ssl %}
+{#
+   If there is a listenning address defined for the insecure TCP listenner,
+   declare it.
+#}
+{% if rabbitmq_conf_tcp_listeners_address != '' %}
+    {tcp_listeners, [{"{{ rabbitmq_conf_tcp_listeners_address }}", {{ rabbitmq_conf_tcp_listeners_port }}}]}{% if rabbitmq_ssl %},
+{% endif %}
+{#
+   Otherwise, shut down the listenner.
+#}
+{% else %}
+    {tcp_listeners, []}{% if rabbitmq_ssl %},
+{% endif %}
+{% endif %}
+{% if rabbitmq_ssl %}
     {ssl_listeners, [{"{{ rabbitmq_conf_ssl_listeners_address }}", {{ rabbitmq_conf_ssl_listeners_port }}}]},
     {ssl_options, [
       {cacertfile, "{{rabbitmq_conf_ssl_options_cacertfile}}"},
@@ -14,6 +23,6 @@
       {verify, verify_peer},
       {fail_if_no_peer_cert,{{rabbitmq_conf_ssl_options_fail_if_no_peer_cert}}}
       ]}
-    {% endif %}
+{% endif %}
   ]}
 ].