update readme with new link

README.md

@@ -18,6 +18,7 @@ See those Stack Overflow answers where this code was used:
 * [why web socket behave differently on nodejs ?](https://stackoverflow.com/questions/39765427/why-web-socket-behave-differently-on-nodejs/39765994#39765994)
 * [getting an error when trying to use socket.io](https://stackoverflow.com/questions/39786269/getting-an-error-when-trying-to-use-socket-io/39786373#39786373)
 * [How to use Socket.io combined with Express.JS](https://stackoverflow.com/questions/40747828/how-to-use-socket-io-combined-with-express-js-using-express-application-generat/40747932#40747932)
+* [Node.js long polling event loop breaks the whole code](https://stackoverflow.com/questions/41210398/node-js-long-polling-event-loop-breaks-the-whole-code/41210763#41210763)
 
 Quick start
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