AMD mode

AMD mode uses https://github.com/jpka/module-investigator instead of node-detective to check for AMD style dependencies, return those if it finds them, else returns the regular CommonJS-style ones. Also it brands each file with a property format that specifies which type of dependency is returning.

I know this is nowhere near a feature intended for this module, but I am submitting it anyway in hopes of avoiding an unnecessary(?) fork. If the fork is indeed necessary, let me know.