This doesn't do any decompression / recompression, but just copies over
the already compressed contents. So it's similar to zip -U, but allows
rewriting of the paths.
The first expected usecase is to replace img_from_target_files during
the build, since it does the equivalent of this:
zip2zip -i <target-files.zip> -o <img.zip> OTA/android-info.txt:android-info.txt IMAGES/*:.
Except it decompresses and recompresses the images, which takes over a
minute instead of a few seconds.
Change-Id: I88d0df188635088783223873f78e193272dbdf1c
