Moved what was in unit_mov branch into behavior branch under
NormalMovement.
Comment 1, move does not need a boolean because there is no error for
it.  A unit will move that direction.  The can move makes sure that the
unit will move there
Comment 2, why are we using a GameModel to move? Shouldn't it be the
unit moving?
Comment 3, Point should go in the shared package alongside physicsvector
which is basically an advanced point with methods.

Also added a few things to Unit to ensure that the move will work.