added link for google groups (#60)

README.md

@@ -1,7 +1,7 @@
 PyDataStructs
 =============
 
-[![Build Status](https://travis-ci.org/codezonediitj/pydatastructs.png?branch=master)](https://travis-ci.org/codezonediitj/pydatastructs) [![Join the chat at https://gitter.im/codezonediitj/pydatastructs](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/codezoned2017/Lobby) [![contributions welcome](https://img.shields.io/badge/contributions-welcome-brightgreen.svg?style=flat)](https://github.com/codezonediitj/pydatastructs/pulls) [![codecov](https://codecov.io/gh/codezonediitj/pydatastructs/branch/master/graph/badge.svg)](https://codecov.io/gh/codezonediitj/pydatastructs)
+[![Build Status](https://travis-ci.org/codezonediitj/pydatastructs.png?branch=master)](https://travis-ci.org/codezonediitj/pydatastructs) [![Join the chat at https://gitter.im/codezonediitj/pydatastructs](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/codezoned2017/Lobby) [![Discuss at [email protected]](https://img.shields.io/badge/discuss-go--github%40googlegroups.com-blue.svg)](https://groups.google.com/forum/#!forum/pydatastructs) [![contributions welcome](https://img.shields.io/badge/contributions-welcome-brightgreen.svg?style=flat)](https://github.com/codezonediitj/pydatastructs/pulls) [![codecov](https://codecov.io/gh/codezonediitj/pydatastructs/branch/master/graph/badge.svg)](https://codecov.io/gh/codezonediitj/pydatastructs)
 
 Who are we?
 -----------