Create AlternativeBoard.java

This seems to work just fine - I am going to finish by implementing the broadside moves this afternoon.
In order to play enter for every move:
the x-coordinate of the last marble [confirm with enter]
the y-coordinate of the last marble [confirm with enter]
the x-coordinate of the direction [confirm with enter]
the y-coordinate of the direction [confirm with enter]

PS: the coordinates start with 0|0 in the upper left corner and go to 8|8 in the bottom right