Added Chat Application Tutorial

Author: sayands

README.md

@@ -139,6 +139,7 @@ To get started, simply fork this repo. Please refer to [CONTRIBUTING.md](CONTRIB
 * [Integrate MailChimp in JS](https://medium.freecodecamp.org/how-to-integrate-mailchimp-in-a-javascript-web-app-2a889fb43f6f)
 * [Build A Chrome Extension with React + Parcel](https://medium.freecodecamp.org/building-chrome-extensions-in-react-parcel-79d0240dd58f)
 * [Build A ToDo App With React Native](https://blog.hasura.io/tutorial-fullstack-react-native-with-graphql-and-authentication-18183d13373a)
+* [Make a Chat Application](https://medium.freecodecamp.org/how-to-build-a-chat-application-using-react-redux-redux-saga-and-web-sockets-47423e4bc21a)
 
 #### Angular: