Feature: add option to `framer new` to default to index.coffee instead of index.js

[WestonThayer]

CoffeeScript is generally the favored language for people using Framer. Let's make it easy to get started using it.

I think this just involves adding an index.coffee to the boilerplate code, and conditionally including it.

[peteschaffner]

When I was using this utility I preferred to write JS mainly because I was more familiar with it, and also to get intelligent completions via Tern (Tern won't work with CoffeeScript).

[WestonThayer]

That makes sense. I still haven't wrapped my head around the autocomplete solutions out there for CoffeeScript, but I think autocomplete is an important feature for most people.

Did you explicitly add support for CoffeeScript or does it just magically work with Browserify?

[peteschaffner]

Intelligent completions for CoffeeScript might be a bit of a headache, and thus one of the big reasons I started using FS, as those guys are working hard on that problem (and doing a damn good job)!

I explicitly added a global CoffeeScript transform.