Ensure zuul's status images are available

Lets apache serve up zuul's status images to fix broken image src's
on http://zuul.openstack.org

Change-Id: Ie3b0ecf6b9d6cfa417f866bbaa8714e8b84ff239

manifests/init.pp

@@ -224,6 +224,12 @@ class zuul (
     require => File['/var/lib/zuul/www'],
   }
 
+  file { '/var/lib/zuul/www/images':
+    ensure  => link,
+    target  => '/opt/zuul/etc/status/public_html/images',
+    require => File['/var/lib/zuul/www'],
+  }
+
   file { '/etc/init.d/zuul':
     ensure => present,
     owner  => 'root',