coverage badge

readme.md

@@ -2,6 +2,7 @@
 
 [![Author](http://img.shields.io/badge/author-@adammbalogh-blue.svg?style=flat)](https://twitter.com/adammbalogh)
 [![Build Status](https://img.shields.io/travis/adammbalogh/key-value-store-memcached/master.svg?style=flat)](https://travis-ci.org/adammbalogh/key-value-store-memcached)
+[![Coverage Status](https://img.shields.io/coveralls/adammbalogh/key-value-store-memcached.svg?style=flat)](https://coveralls.io/r/adammbalogh/key-value-store-memcached)
 [![Quality Score](https://img.shields.io/scrutinizer/g/adammbalogh/key-value-store-memcached.svg?style=flat)](https://scrutinizer-ci.com/g/adammbalogh/key-value-store-memcached)
 [![Software License](https://img.shields.io/badge/license-MIT-blue.svg?style=flat)](LICENSE)
 [![Packagist Version](https://img.shields.io/packagist/v/adammbalogh/key-value-store-memcached.svg?style=flat)](https://packagist.org/packages/adammbalogh/key-value-store-memcached)