router.go
func (rm *routeMap) add(method, pattern string, leaf *Leaf) {
	rm.lock.Lock()
	defer rm.lock.Unlock()

	rm.routes[method][pattern] = leaf
}
func (rm *routeMap) add(method, pattern string, leaf *Leaf) {
	rm.lock.Lock()
	defer rm.lock.Unlock()

	rm.routes[method][pattern] = leaf
}
// add adds new route to route tree map.