[sugar] PlayGo v2 and v3

[Ties Stuij]

Cool to see PlayGo is making progress!

some notes:
- when playing against GnuGo, restarting a saved board will put you in
hotseat mode. Would of course be nice to play against the computer
again.
- in general would be nice if one can switch from hotseat mode to
GnuGo-mode with the current configuration intact.
- on an xo, a 19x19 board becomes rather small with the current
layout. I'd put all the info next to the board, in stead of beneath,
like it was in the original PlayGo.
- when playing against GnuGo, the board is updated only after the cpu
has done it's move. I'd update the board after your move and before
you give the reigns to GnuGo; to give people something to look at.
- two xo's head to head works like a charm

/Ties