HW2: 1st commit.
(1). Update GameApi
(2). AbaloneLogicTest: change Set(TURN, WP) to SetTurn(wId)
(3). AbaloneLogicTest: change jump format to List<List<List<Integer>>>
to reduce the format transformations.
(4). Add AbaloneConstants to store all constants for Abalone game.
(5). Enum Square to represent four state of each square on board
(6). Enum Turn to represent turn for WP & BP
(7). AbaloneUtilities to store all static methods
(8). AbaloneState to store the game state: turn, board, jump.