Override hashCode in Position
Add getAllAvailableCaptures method in RuleManager + test

This method returns all captures that can be currently made by a player.
Change return type in getAvailableCaptures in RuleManager

This method now returns a Set.
Add size field to the Board
Add signatures for methods for getting available moves + add unit tests
Change method arguments in RuleManager

int[][] board -> Board board
Implement methods for getting available moves

Also slightly corrected tests.