game_card.rb line 73 checks if players >1, this should check against the actual game

I'm very surprised nobody has placed a request for this but Sabaki definitely needs this. Because squinting your eyes to correctly place a stone using a mouse on the goban is ridiculous in my opinion and this ghost stone feature would greatly help. Once,this feature is selected then seeing a ghost stone on the board would greatly enhance accuracy in placing stones on the goban. Just like KGS, OGS