Document LOCATION_CHANGE action type

Author: dandelany

README.md

@@ -174,3 +174,7 @@ These action creators are also available in one single object as `routerActions`
 #### `routerMiddleware(history)`
 
 A middleware you can apply to your Redux `store` to capture dispatched actions created by the action creators. It will redirect those actions to the provided `history` instance.
+
+#### `LOCATION_CHANGE`
+
+An action type that you can listen for in your reducers to be notified of route updates. Fires *after* any changes to history.