JavaScript

I've started very, very preliminary work on a JavaScript tutorial, [here](https://github.com/adambrenecki/learnxinyminutes-docs/blob/javascript/javascript.html.markdown). It's not ready to merge just yet, but I thought I'd create this issue in case someone else wants to work on JS too, to track the process.

Do let me know whether this is the sort of thing you're after, though.