feat: add PATCH method to Kite and Group

- Add PATCH(path, handler, ...middleware) on Kite for top-level routes
- Add PATCH(path, handler, ...middleware) on Group for nested routes

kite.go

@@ -227,6 +227,10 @@ func (k *Kite) OPTIONS(path string, h Handler, mws ...Middleware) {
 	k.handle(http.MethodOptions, path, h, mws...)
 }
 
+func (k *Kite) PATCH(path string, h Handler, mws ...Middleware) {
+	k.handle(http.MethodPatch, path, h, mws...)
+}
+
 func (k *Kite) POST(path string, h Handler, mws ...Middleware) {
 	k.handle(http.MethodPost, path, h, mws...)
 }