Fix badges

Author: discordier

README.md

@@ -1,4 +1,5 @@
-[![Build Status](https://travis-ci.org/MetaModels/filter_range.svg)](https://travis-ci.org/MetaModels/filter_range)
+[![Stable Build Status](http://img.shields.io/travis/MetaModels/filter_range/master.svg?label=stable)](https://travis-ci.org/MetaModels/filter_range/branches)
+[![Development Build Status](http://img.shields.io/travis/MetaModels/filter_range/develop.svg?label=develop)](https://travis-ci.org/MetaModels/filter_range/branches)
 [![Latest Version tagged](http://img.shields.io/github/tag/MetaModels/filter_range.svg)](https://github.com/MetaModels/filter_range/tags)
 [![Latest Version on Packagist](http://img.shields.io/packagist/v/MetaModels/filter_range.svg)](https://packagist.org/packages/MetaModels/filter_range)
 [![Installations via composer per month](http://img.shields.io/packagist/dm/MetaModels/filter_range.svg)](https://packagist.org/packages/MetaModels/filter_range)