Yaf_Route_Simple will match the query string, and find the route info.
all you need to do is tell Yaf_Route_Simple what key in the $_GET is module, what key is controller, and what key is action.
Yaf_Route_Simple::route() will always return
so it is important put Yaf_Route_Simple in the front of the Route stack,
otherwise all the other routes will not be called.