Added loading of JSHint config

Hey,

I've noticed that this feature was missing (https://github.com/addyosmani/sublime-fixmyjs/issues/2) and I really needed this feature, so i did my best and implemented it.
If it needs more polishing, just say :-)
That's just confusing for anyone looking as it's not an JSHint option. Better to get fixmyjs to support for their own options. The legacy option is hopefully going away soon anyway.