postfix: Use base::postfix::sender

manifests/postfix.pp

@@ -54,11 +54,16 @@ class base::postfix {
     '/etc/postfix/recipients':
       ensure  => present;
     '/etc/postfix/senders':
-      content => "root@stanford.edu root@${::hostname}\n";
+      ensure  => present;
     '/etc/postfix/transport':
       source  => 'puppet:///modules/base/postfix/etc/postfix/transport';
   }
 
+  # Have mail from root@stanford.edu come from root at the local system
+  base::postfix::sender { 'root@stanford.edu':
+    ensure => "root@${::hostname}";
+  }
+
   # We used to disable and stop sendmail here on Red Hat, but this doesn't
   # work if sendmail is not installed.  Since we'd rather not have sendmail
   # installed, just assume that people are doing this manually.