[GATE-3] Still working on buddy add/remove issues.  More code cleanup here and there and improvements to connection status handling.  Per gato's great suggestion, switched some hashs to concurrent hashes to dodge concurrent modification exceptions.

git-svn-id: http://svn.igniterealtime.org/svn/repos/wildfire/trunk/src/plugins/gateway@5267 b35dd754-fafc-0310-a699-88a17e54d16e