ACF: Reduce computer hog levels in missions 2 and 6.
They were way too high, especially in mission 2.
Mission 2:
Weaklings: level 5 → level 1 (except Brainiac)
Stronglings: (real) level 4 → level 2
Brainiac: level 1 → level 5 (because he's special)
Looks like all levels were just flipped.
Mission 5:
First enemy team: level 5 → level 3
Reinforcements: level 5 → level 4
The high skill level punishes player mistakes too much.
07f3bf8d98a3
Hedgewars.png had a resolution more than twice as high as required; also fixed some (mostly obsolete) code that also contained a typo that would cause a warning/note in clang
