#16 Merge .d2x for search reasons

[Tymur]

It would be a greate improvement to have a possibility to merge in the output the Stashs (without actually do merging different .d2x files), so you can view some set1.d2x, set2.d2x and items.d2x as one stash to find out the right item, but have the set-stashs as different files.