Add Starting Position For Chess Piece

Add starting position for chess pieces because pawns can only go one
way and in order to tell which way they are going either up or down,
there needs to be a starting position for them.
Both Pawns Are Using Same Code When Moving

Both white and black pawn are using the same code when moving because
pawns can only go one way so it would not make sense to have two
separated code doing the same thing.
Add Check If Cells Are Empty Front Of Chess Piece

Add in a function in chess move class to check if the cells in front of
a chess piece are empty. Because pawns only can go one way, however
they cannot kill what is in front of them. This check will make sure
there is only empty spaces up until a chess piece is found or the
number of moves that are allowed are used up.