This is now an horizontal action Arkanoid without bricks.
- Removed all remainders of 2-player action (closes #13);
- Added a basic lives system. You lose a life when you lose a ball (closes #12), end of game by match points is no longer supported (closes #7).
- Added a couple of comments here and there with new findings so that I won't forget.

Next commit is expected to transpose and enlarge the bar for finishing issues #6 & #9 and make the game vertical for issue #15

Compilation tests: Pass (@ Symphony EDA Sonata 3.0). Unable to make a simulation for it until I have the FPGA board for testing.

Signed-off-by: jaBote <javote91@hotmail.com>