Merge filter and notification servers, have both tasks run on the same servers

modules/notificationserver/manifests/init.pp

-class notificationserver {
-  class {'nginx':
-    worker_processes => 2,
-    worker_connections => 4000,
-    ssl_session_cache => off,
+class notificationserver($is_default = false) {
+  if !defined(Class['nginx']) {
+    class {'nginx':
+      worker_processes => 2,
+      worker_connections => 4000,
+      ssl_session_cache => off,
+    }
+  }
+
+  if !defined(File['/var/www']) {
+    file {'/var/www':
+      ensure => directory,
+      owner => nginx,
+      mode => 0755,
+      require => Package['nginx']
+    }
   }
 
   class {'sitescripts':
     sitescriptsini_source => 'puppet:///modules/notificationserver/sitescripts.ini'
   }
 
-  file {'/var/www':
-    ensure => directory,
-    owner => nginx,
-    mode => 0755,
-    require => Package['nginx']
-  }
-
   file {'/var/www/notification':
     ensure => directory,
     owner => nginx,
     mode => 0755,
     require => Package['nginx']
   }
 
   exec { "fetch_notifications":
     command => "hg clone --noupdate https://hg.adblockplus.org/notifications /opt/notifications && chown -R nginx /opt/notifications",
     path => ["/usr/bin/", "/bin/"],
@@ skipping 32 matching lines @@
 
   file {'/etc/nginx/sites-available/adblockplus.org_sslcert.pem':
     ensure => file,
     notify => Service['nginx'],
     before => Nginx::Hostconfig['notification.adblockplus.org'],
     mode => 0400,
     source => 'puppet:///modules/private/adblockplus.org_sslcert.pem'
   }
 
   nginx::hostconfig{'notification.adblockplus.org':
-    source => 'puppet:///modules/notificationserver/notification.adblockplus.org',
+    content => template('notificationserver/notification.adblockplus.org.erb'),
     enabled => true
   }
 
   file {'/etc/logrotate.d/nginx_notification.adblockplus.org':
     ensure => file,
     mode => 0444,
     require => Nginx::Hostconfig['notification.adblockplus.org'],
     source => 'puppet:///modules/notificationserver/logrotate'
   }
 }