[RMG]Fix gcc build, remove some unused variables
- Zone guards will now match template settings.
- Added guards for monoliths.
- fixed mantis #783 - play sound when entering message in chat box
Zone position will be moved to its center of mass.
Merge branch 'develop' of https://github.com/vcmi/vcmi into RMG
Merge branch 'develop' of https://github.com/vcmi/vcmi into RMG