= IWAD patches

Just some VCDIFF files for upgrading/downgrading between various IWAD
releases without having to use DOS patchers (which are both slow and
somewhat difficult to run).  VCDIFF is a binary patch standard,
probably most common with xdelta3, but any program that supports them
would work.

An example for upgrading plutonia.wad to the id Anthology version:

....
$ cd plutonia.wad
$ xdelta3 -d -s plutonia.wad 1.9-to-anthology.vcdiff plutonia-anth.wad
....