added a way to get the symmetry of the map

This code can really be dropped into any player that you currently have written. Given the location of ourBase, the opponent's base, and the representation of the map, it will tell you whether the map has horizontal, vertical, transpose (diagonally down), or alternative (diagonally up) symmetry, whether one side is rotated 180 degrees from the other and which corner ourBase is in (necessary to find the symmetry).