func (mx *Mux) Trace(pattern string, handlerFn http.HandlerFunc) {
	mx.handle(mTRACE, pattern, handlerFn)
}
func (mx *Mux) Trace(pattern string, handlerFn http.HandlerFunc) {
	mx.handle(mTRACE, pattern, handlerFn)
}
// Trace adds the route `pattern` that matches a TRACE http method to
// execute the `handlerFn` http.HandlerFunc.