-fixed c119 and ah1g ai orbit failing occasionally, and losing altitude

quality of life update

-tweaked zombie spawn logic to increase spread and avoid too many zombies spawning in the same place
-added out of bounds volumes to teleport players back to game area
-tweaked level objects to fix holes bypassing blockers
-reduced slots to 6 to fit the 4 player + 2 design vision

* added fire supports
* ac119 gunship
* ah1g cobra gunship
* scripted napalm barrage
* random turret crate delivery
* 3 man reinforcements
* adjusted price of fire support station (was 3000, now 30 000)
* changed location and icon of fire support station
* adjusted position, price and ammo of kozlice shotgun station
* fixed a no-go zone for zombies who were phasing through walls of barracks