Notify apache2 reload on updates to mirror vhost

Reflect changes to mirror vhost configs immediately in their running
Apache services by notifying a new reload handler.

Change-Id: Ib3c9560781116f94b0fdfc56dfa5df3a1af74113

playbooks/roles/mirror/handlers/main.yaml

@@ -2,3 +2,8 @@
   service:
     name: apache2
     state: restarted
+
+- name: reload apache2
+  service:
+    name: apache2
+    state: reloaded

playbooks/roles/mirror/tasks/main.yaml

@@ -141,6 +141,8 @@
   template:
     src: mirror.vhost.j2
     dest: /etc/apache2/sites-available/mirror.conf
+  notify:
+    - reload apache2
 
 - name: Make sure default site disabled
   command: a2dissite 000-default.conf