#44 Move UserList into Channel

[David M. Johnson]

Take a look at how org.relayirc.swingui.ChannelPanel
handles onJoins(), onJoin() and onPart() ChannelPanel
user a UserList class to handle the actual list. This
stuff should really be moved into the ChatEngine's
Channel class itself instead of the Swing UI module.

[David M. Johnson]

Logged In: YES
user_id=1238

That way, Channel could have a getUsers() method.