Add implicit cjsx support, add basic test files, add .gitignore for node...

..._modules

Hey @TrevorBurnham, I'd like to add `.cjsx` support to this via `coffee-react`.  `coffee-react` acts as a wrapper for coffee so if a file is .cjsx it'll compile it, otherwise it'll hand it off to `coffee-script`.

Right now this is an implicit check for `coffee-react`.  If you think this feature would be better as a flag that would be added I'd be happy to rewrite this.

I also added some test files to mess with, but I didn't add any actual test files.  I'm not sure if you have a favorite test framework that you'd want to use.