Support Go about fairy-stockfish

[PraseodymiumSpike]

Actually, you could make any play that captures any of your own pieces illegal. This would make it so pieces can't capture royal pieces if that would result in the capturing piece's instant capture, though.

[osmiumic]

i'd like to note that not all variants of Go make self-capture illegal. very occasionally, there is a tactical situation where self-capture is better from what i remember reading about it. (i also play Go as a hobby)