Facilitated non-symmetric playable area within the array
-Replaced defined constants VERTICAL_MARGIN, HORIZONTAL_MARGIN, VERTICAL_END, and HORIZONTAL_END with TOP_MARGIN, BOTTOM_MARGIN, LEFT_MARGIN, RIGHT_MARGIN, BOTTOM_END, and RIGHT_END. With these we may specify the area of the array that the playable area will occupy without it being symmetric about both axes. For example, we could increase only the top margin to present score.
 On branch master
	modified:   hidev/pong.c