When a patch version is released, it must declare compatibility with the
previous patch versions of the same main release. This allows players to
keep replaying their games and to keep playing online with users of
other patches of the same main release.
This should have anticipated for dae7a8c394
Also drop build version component as we never used it in earlier
releases either. This will also make replays et al be stored in a
directory 0.27.0 similar to earlier releases.
The build version component was introduced in 028ec40165
Signed-off-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
