* IMPROVED: Stop the weblog demo server upon halting Prolog.
* IMPROVED: Use prolog:message//1 for server stopped message. Also displaying the port number now.
* CLEANUP: Removed bye/0 which used to (1) stop the weblog demo server and (2) halt Prolog. Now halting Prolog also stops the server (if any).
* CLEANUP: Renamed start/0 to start_server/0 for consistency with stop_server/0.