Mac version released

Today we are releasing a new version for MacOS. 

Also, included are a few improvments from 1.0:

• Merc Tactics now requires  OpenGL 3.2 as minimum (required for MacOS)
•  Some graphics performance improvements
• Enemy adopts new pose when in overwatch, making it easier to see he is trying to interrupt.
•  Improved AI behaviour: AI abandons overwatch after being hit 
•  Some improvements in help 
• Bug fix: prevent moving during AI interrupt 
• Bug fix: unexpected combatant in path 
• Bug fix: roof not being removed in time