Adding websockets via SockJS

@vzvenyach This should provide an example of how to work with websockets for communication between client and server. There is a method on the server to communicate to an individual socket and to all sockets at once. You can pass any JSON object, it just gets stringified when sent. 

This works on localhost, but haven't tested on Heroku. You'll need to change this line in index.html 

> var socket = new SockJS('http://localhost:5000/sockjs');

to point to the correct location for Heroku and then it should work.