Hotfix 0.86b

Just a quick hotfix to the yesterday patch:

Fixed:
- Fixed time rewind exploit.
- Fixed undead master ability.
- Few AI improvements.
- Game should run in a background.

Balance:
- Domownik now gives strenght bonus only to itself.
- Shoes price reduced to 1.
- Shoes effect changed to: "Fallback: gain 1 action".
- Axeman (level 3): strength -1.
- Sword-bearer (level 3): strength -1.
- Sword-bearer: now is getting +1 strengt only when other unit uses a skill.
- Tier 2 Forsaken Giant battle: Kite shield replaced by blessed helmet.