GameInstance,TicTacToe  changed, see details

////GameInstance:
-- Added variables activePlayer and turns
-- Added checks to see if cell was free, if so then the move proceeds
and turns get raised and active player is changed.
--Added functions to get active player and turns

////TicTacToe
--clickField now returns gamestatus, activeplaer and turn
-- resetGame now resets activeplayer and turns.