Break out color_check logic from SlidingPiece class for use by other pieces.
Add Pawn move method and fix rendering.
Removes needs for moves to take a position argument.
Correct logic for in_check?
Adds deep_dup method and adds place piece method.
Adds move_into_check?(pos) method.
Fix duping pieces. Create method to call a move using a position in array format.
Correct valid_moves to only return moves that do not put player in check.
Creates unsafe move method and checkmate testing method.
Fixes checkmate?(color) function.
Adds play function to Chess class as well as subfunctions within the play function.
First working version.
Post-code review refactoring.
Fix Error raising throughout project.