CoffeeScript should be a dependency

[wookiehangover]

So it's kinda hard to use this programmatically if you need to rely on CoffeeScript to be in your global path or a pre-existing peer dependency in local node_modules.

Happy to issue you a pull if you'd like, but this is a pretty simple fix:

npm install --save coffee-script

A version bump, commit and npm publish and...Voila, people won't get stupid install errors from npm

Cheers! :ghost: