SC2Mapster

- Now 5 upgrades for Humans instead of 3.
- Rebalanced the Super Zombies' health to 120, up from 100.
- Added timed upgrades for Zombies and Super Zombies, to match the progression of Humans.
- Added a fourth entrance to the upper level of the Human spawn, to make it more difficult to defend.
- Added something else, but players will have to find that for themselves.
- Fixed a bug causing the game to end when there were still Humans alive.