Convoy Fixes

Infantry swarm around fortified positions and convoys now randomly move
around.
Sochi airfield assault added

rough around the edges but something new to do, will need to do the
other airfields as well and work on a way to check damage done in the
area (probably mist function to check for dead polys in a trigger zone)
Merge pull request #6 from chameleonsilk/master

Sync