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README.md

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-# ES6-Promise (subset of [rsvp.js](https://github.com/tildeio/rsvp.js))
+# ES6-Promise (subset of [rsvp.js](https://github.com/tildeio/rsvp.js)) [![Build Status](https://travis-ci.org/stefanpenner/es6-promise.svg?branch=master)](https://travis-ci.org/stefanpenner/es6-promise)
 
 This is a polyfill of the [ES6 Promise](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-promise-constructor). The implementation is a subset of [rsvp.js](https://github.com/tildeio/rsvp.js) extracted by @jakearchibald, if you're wanting extra features and more debugging options, check out the [full library](https://github.com/tildeio/rsvp.js).