Echo JS 0.11.0

There are unfortunately some formatting issues... part of the HTML markup is posted twice, and the markdown code formatting towards the end seems to be entirely broken.

As to the content, it all seems relatively straight forward, until it breaks...

I do think it might have been better served by not introducing all the concepts in play at once...  Starting with a very basic, single instance websocket server.  Then explain the shortcomings and how sticky sessions are provided by socket.io, along with channels/routing.  Then expressing the issues with connection scaling, and adding in cluster and the redis adapter.  Why adding a worker on the server helps, etc.

Those last bits are actually questionable for the use case in question, as most bottlenecking will become IO bound on Redis, and cluster/worker may not add much as Node.js uses thread pooling for IO connections.

That said, by starting simple, and adding the extra bits, it becomes possible to separate some of the conceptual pieces that can overload someone not already familiar with those pieces and the why behind them.  Also, a github repo that has commits on master matching the stages of the project would also be very beneficial.