docs: Update readme

CasperLaiTW · CasperLaiTW · commit d2aba29f496e · 2017-06-28T16:16:13.000+08:00
diff --git a/README.md b/README.md
@@ -186,8 +186,8 @@ The debug route using [Pusher](https://pusher.com/)
   APP_DEBUG=true
   BROADCAST_DRIVER=pusher
   PUSHER_APP_ID=
-  PUSHER_KEY=
-  PUSHER_SECRET=
+  PUSHER_APP_KEY=
+  PUSHER_APP_SECRET=
 ```
 
 ### Publish script
