Indentation

[simonfan]

Hey! Just to inform that the json indentation is not working.. I just needed a quick solution for that, so just added support for JSON.stringify(data, replacer, space) in both jsonFile.write(callback, replacer, space) and json.writeSync(replacer, space).

The indentation autodetection is a nice idea! But I think it is a good idea to expose JSON.stringify native functionalities.

I'll make a pull request for that simple change..

Thank you!