OF-616: Public Group cache should be refreshed after a group is added.

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@13490 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/group/GroupManager.java

@@ -102,6 +102,7 @@ public class GroupManager {
                 groupMetaCache.remove(GROUP_COUNT_KEY);
                 groupMetaCache.remove(GROUP_NAMES_KEY);
                 groupMetaCache.remove(SHARED_GROUPS_KEY);
+                groupMetaCache.remove(PUBLIC_GROUPS);
 
                 // Evict cached information for affected users
                 evictCachedUsersForGroup(group);