Currently when I unzip into a directory with pre-existing files, I sometimes unzip an archive to update the files, using -f or -u or -o to overwrite any clashes.
However I would like the unzip process to also delete any files which were not part of the archive, so that the unzipped version fully matches what was in the zipped archive. (Why not just replace the directory then with a fresh unzip? Because I still want to preserve .svn files, just wipe everything else)
