chd format

[etabeta]

I will eventually give t7z a try.

I guess that since pakkiso has been abandoned there is not much point into make it work better on MacOSX... too bad, because pakkiso worked pretty well for sets with 1-2 files through CrossOver/WINE and my script has its own weak points (mainly about disk space usage, since it copies the files before acting on them)

However, I can also easily see why t7z is preferred when you have to update sets

Thanks for the feedback.