Fix bug in random flyby and civilian drive bys

New features:
* Ensure enemy don't spawn near the landing zone. Enemy shouldn't be too near the landing zone anymore.
* Single player pausing: When playing solo (and not on a dedicated server) you will have the option on the mousewheel to pause the game once it's started.
* Improvements for night missions

. add option for target and extra guys w/o rifle (pistol in holster at start)
. add option to end at reaching chopper
. added suppressors to the ammo create
. don't show photos of targets if the targets are already dead
. make sure no civilians or enemy are wearing beret except targets

Changed it so the players are invisible to the AI until they land on the ground at the start. Make sure your start location is quite a ways from any of the target areas to ensure you can infiltrate safely.