The OnTimeout event handler is invoked after the client has
has exceeded the maximum allowed idle time. To implement
an event handler, the application should create a class derived from
the CHttpServer class, and then override this method.
This event handler will be invoked prior to the client being
disconnected from the server. This event will never
occur while the server is returning data to the client. The
SetClientIdleTime method can be used to change or refresh the idle
timeout period for the session.