Code for adding and saving group aliases

Added code to add and save group aliases. Like tags, aliases are
free-texted in to the group admin page. configurable max number of
aliases, default is three.

lib/common.php

@@ -198,6 +198,8 @@ $config =
         'user_quota' => 50000000,
         'monthly_quota' => 15000000,
         ),
+        'group' =>
+        array('maxaliases' => 3),
         );
 
 $config['db'] = &PEAR::getStaticProperty('DB_DataObject','options');