Port PEG JavaScript to CoffeeScript.

This is my first attempt at porting one of these.

The basic concept is that there is a CoffeeScript class whose instance methods each map to a rule in the grammar.

I went with this approach over other "use CoffeeScript with PEG" methods [[1](https://github.com/Dignifiedquire/pegjs-coffee-plugin)][[2](https://github.com/ttilley/pegcoffee)] since they affected the unlying way that PEG works.

All of the test pass, but I figured that there might be some things to discuss regarding naming or the API. In general, I tried to refactor or rename things to be more explicit and easier to understand.

FWIW - I tried to push directly to a feature branch on the-gss/ccss-compiler but got an error about not having the correct access.