Moving npm package upstream

As convenient as `git` and GitHub make maintaining a very lightweight fork (virtually no modifications to existing code), I think it's time to fold my `npm` package back into the core.

Since the project is a Python/JS hybrid, of sorts, I did not follow the conventional `npm` source organization (`bin` and `lib` dirs, etc). These are things we can decide later, if desired (they're not required, just convention).

Lamentably, I have not written tests for the CLI interface I wrote (though I have exhaustively tested it in practice). This is largely because of the difficulty of integrating the existing functional tests with a convenient npm-based test framework like [Mocha](http://visionmedia.github.com/mocha/) or [Vows](http://vowsjs.org/). I have experience with both frameworks, and am willing to contribute framework-based tests in the future.

Following the `npm` convention, the existing tests can be run via `npm test` in the project root. (Controlled by the `scripts` property of [package.json](https://npmjs.org/doc/json.html))

Once merged, we'll need to modify the `repository.url` and possibly the `contributors` list (I just pulled what I could find from `index.html` and the `README`. As long as we're still using the `js-beautify` package identifier for `npm`, I can add @einars and @bitwiseman as [owners](https://npmjs.org/doc/owner.html) (after you create accounts via `npm`'s [adduser](https://npmjs.org/doc/adduser.html) subcommand), which would allow you to publish new versions to the npm [registry](https://npmjs.org/doc/registry.html).

I would be happy to effect these changes in the core repo directly, if you're willing to give me contributor access. Otherwise, I'll just make another pull request (adding ownership regardless).