Remove gitter link

README.md

@@ -1,4 +1,4 @@
-Whiteout Mail [![Build Status](https://travis-ci.org/whiteout-io/mail.svg?branch=master)](https://travis-ci.org/whiteout-io/mail) [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/whiteout-io/mail?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+Whiteout Mail [![Build Status](https://travis-ci.org/whiteout-io/mail.svg?branch=master)](https://travis-ci.org/whiteout-io/mail)
 ==========
 
 Whiteout Mail is an easy to use email client with integrated OpenPGP encryption written in pure JavaScript. Download the official version under [whiteout.io](https://whiteout.io/#product).