Let the user provider limit the result set rather than getting everyone, then limiting it ourselves. This should speed things up. Also remove some dead code that would have crashed if it ever ran. For http://jira.jiveland.com/browse/CS-4034, reviewed by Armando and Gato

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@10226 b35dd754-fafc-0310-a699-88a17e54d16e