Demo simplified and slightly expanded

[karaokeresearch]

Thank you for writing this. Very useful piece of software. I have some proposed changes for the client:

Switched out the complicated Express code in app.js for express.static middleware. Switched to port 80 to ease mobile testing.

In the index.html, I use the version-independent syntax and ditch the standalone socket.io.js file in favor of having it served out by socket.io