New node-local.js

[Austin Cheney]

This is for anybody who uses Pretty Diff with node.js.

I have written a new node-local.js file almost completely from scratch. It is almost entirely asynchronous is every logic decision (file system interaction is completely asynchronous) and this new file is capable of walking entire directory trees provided an option of "readmethod" with new values "auto" or "subdirectory".

Please test it out. It should do more, do it faster, and do it with less code that is easier to read than the older file.

https://gist.github.com/austincheney/8bec07083026952e3723

Thanks,
Austin