Map cs_extraction for cs 1.6

Cs_extraction - Rescue by [Spacepimp]William_Shatner aka JayGleig@shaw.ca and special thanks to Sid_the_Vivar Counter-Terrorists: Rescue the downed airmen and return to the extraction point while avoiding Terrorist ambush and holding extraction point from terrorist bombing. Terrorists: Prevent rescue of airman by eliminating CT force or bombing extraction point. (Press FIRE to continue)