Add url_path documention for detail_route decorator

Author: tanwanirahul

docs/tutorial/6-viewsets-and-routers.md

@@ -53,6 +53,8 @@ Notice that we've also used the `@detail_route` decorator to create a custom act
 
 Custom actions which use the `@detail_route` decorator will respond to `GET` requests.  We can use the `methods` argument if we wanted an action that responded to `POST` requests.
 
+The URLs for custom actions by default depends on the method name itself. If you want to change the way url should be constructed, you can use `url_path` parameter of `@detail_route` and provide the string value for the same.
+
 ## Binding ViewSets to URLs explicitly
 
 The handler methods only get bound to the actions when we define the URLConf.