add a parameter to turn off mongod journal

closes: #68

manifests/database/nosql.pp

@@ -19,6 +19,7 @@
 #
 class cloud::database::nosql(
   $bind_ip   = undef,
+  $nojournal = $os_params::mongodb_nojournal,
 ) {
 
   # use mongo's own repo instead of the distro's
@@ -27,6 +28,7 @@ class cloud::database::nosql(
   }->
   class { 'mongodb':
     bind_ip => $bind_ip,
+    nojournal => $nojournal,
   }
 
 }