Extinction Chess

[alexobviously]

http://www.chessvariants.org/winning.dir/extinction.html

The loser is the first player to not have at least 1 of every piece type on the board. This is achievable with ActionCheckPieceCount, but will also suffer from bug #65, so it would be good to fix that first, and maybe provide a better action for many pieces, or at least a helper function (ActionCheckPieceCount.multi() or something).