Point users to #rackt on freenode for chat

Fixes #2250

Author: mjackson

README.md

@@ -1,6 +1,6 @@
 [![build status](https://img.shields.io/travis/rackt/react-router/master.svg?style=flat-square)](https://travis-ci.org/rackt/react-router)
 [![npm package](https://img.shields.io/npm/v/react-router.svg?style=flat-square)](https://www.npmjs.org/package/react-router)
-[![react-router channel on slack](https://img.shields.io/badge/slack-react--router@reactiflux-61DAFB.svg?style=flat-square)](http://www.reactiflux.com)
+[![#rackt on freenode](https://img.shields.io/badge/irc-rackt_on_freenode-61DAFB.svg?style=flat-square)](https://webchat.freenode.net/)
 
 <img src="https://rackt.github.io/react-router/img/vertical.png" width="300"/>