coffeescript rewrite

When I started writing jetzt, I didn't expect it to become a compelling long-term project for me. It was just a two-day hackathon type thing to implement a version of Spritz I could use to read stuff on [project gutenberg](http://www.gutenberg.org/). I chose Javascript because I'd been using it a lot for work recently, and was sure I could conjure up something fast.

Now, however, I've got some rather grand plans for jetzt, but have been dreading working on the codebase because I actually find Javascript very tedious to write. Coffeescript is still quite new to me (I'm mostly a clojure/java guy), but it solves pretty much everything I dislike about Javascript, so I'm going to start a re-write on another branch.

I hope this doesn't upset those of you who have invested time and effort into the project so far. It has all been valuable input, I assure you, and I hope that you will continue to contribute.

Start by reviewing the existing JavaScript codebase and the proposed CoffeeScript rewrite branch. The issue names no files, tests, or entry points, so first identify the migration scope and how the project is built. Done would require an agreed, complete rewrite with the existing project behavior preserved.

Written by the indexing model from the issue text.