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README.md

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-# reveal.js [![Build Status](https://travis-ci.org/hakimel/reveal.js.png)](https://travis-ci.org/hakimel/reveal.js)
+# reveal.js [![Build Status](https://travis-ci.org/hakimel/reveal.js.png?branch=master)](https://travis-ci.org/hakimel/reveal.js)
 
 A framework for easily creating beautiful presentations using HTML. [Check out the live demo](http://lab.hakim.se/reveal-js/).