* BattleAI will restore callback to its previous state, fixes freeze after battle #1104
* BattleAI won't lose turn when unable to correctly evaluate a spell
* VCAI will correctly recognize hero standing on town entrance
* War machines of defender will have correctly set side
* Faction 9 as neutral causes crashes, changing to -1 as used elsewhere in the code
* battle AIs receive ptr to CBattleCallback (not sure why it was CPlayerBattleCallback, likely mistake)
* reworked some battle callback methods to be more generic and able to handle some hypothetic scenarios
* for testing purposes in duel mode the first AI will be taken fro mconfig and the second will remain stupid ai
* minor changes