Added board state functions.
Added collapse button and CSS fixes.
Fixed validation logic.
Added partial gameplay functionality.
Implemented a win condition check.
Added partial handling of tie conditions.
Changed how moves are made so players don't directly interact with the board.
Fixed a couple of missing references to 'this'.
Modified victory condition to use GMP, since PHP doesn't like 64-bit ints.
Fixed issue with decimal rounding.
Added a turn identifier.