Expose more bsdiff internals

It seems both https://github.com/thoughtpolice/minibsdiff and this project try to do similar things. Is there a chance that the api could be expanded a bit to allow custom compression algos?

Thanks for the suggestion! I haven't heard of minibsdiff before, so I'll check it out.