builds a 2048 starting board 
    Printing Grid
     0     0     0     2
     0     0     4     0
     0     0     0     0
     0     0     0     0

def build_board_2048():
    """ builds a 2048 starting board 
    Printing Grid
     0     0     0     2
     0     0     4     0
     0     0     0     0
     0     0     0     0

    """
    grd = Grid(4,4, [2,4])
    grd.new_tile()
    grd.new_tile()
    print(grd)
    return grd