using travis icon for master branch

Author: neu-rah

README.md

@@ -3,7 +3,7 @@
 **Generic menu/interactivity system**
 
 [![License: CC BY-NC-SA 4.0](https://img.shields.io/badge/License-CC%20BY--NC--SA%204.0-lightgrey.svg)](http://creativecommons.org/licenses/by-nc-sa/4.0/)
-[![Build Status](https://travis-ci.org/neu-rah/ArduinoMenu.svg?branch=dev)](https://travis-ci.org/neu-rah/ArduinoMenu)
+[![Build Status](https://travis-ci.org/neu-rah/ArduinoMenu.svg?branch=master)](https://travis-ci.org/neu-rah/ArduinoMenu)
 [![Donate](https://img.shields.io/badge/Donate-PayPal-green.svg)](https://www.paypal.me/ruihfazevedo)
 [![Join Gitter](https://img.shields.io/badge/GITTER-join%20chat-green.svg)](https://gitter.im/ArduinoMenu/Lobby)