* all lock/unlock and unlock/lock pairs are done by RAII guards now
* fixed two possible crashes at the end of battle when last stack was killed by spell. That should fix#749 and #752.
* fixed a very nasty race condition, eliminating possible deadlock at the start of battle when human hero has tactics
* fixed#422
* spells learning
* no tooltips for objects under FoW
* working resource silo
* new system for simple unit abilities/states
* neutral monster army disappears when defeated
* synchronization between client and server processes
* fixed battle ending