Prevent move repetitions for chess

[oggy22]

Make minmax algorithm avoid the repetition. The following checks can be performed
if move(1)==move(5) and
move(2)==move(6) and
move(3)==move(7) and
move(4)==move(8)
do not make move(4)

move(n) = the last n-th move. For example move(1) is the last move the opponent made, move(2) is the last move the current player made.