New scheme to deal with listeners, there is a Listener object for each listener encap...

New scheme to deal with listeners, there is a Listener object for each listener encapsulating the logic for stopping and starting that used to be in Server.refresh_config(), listeners are stored in Resources object with a reference count, Server.start()/stop()/kick() are called on configuration change/timer, which may or may not call each Listener.start()/stop() depending on the reference counts