Complete working version for L4D2

I previously packaged a different version (v4) that worked correctly in co-op and versus with no missing textures since the only version previously posted here had a number of problems, and at one point had no versus mode.  Herbius made at least four updates today (version still shows 1.0), that fixes all the issues I was aware of, so I removed (abandoned) the hack I did (using modifications apparently made by Herbius and others).

The original L4D1 map was created by Hunter McJesus, and this L4D2 modified/ported version done by Herbius works great now.  No missing textures (purple areas), and it works without any major issues in co-op and versus modes.  I really like this map, particularly the challenge of so many places where you can fall off ledges.  Some maps may not have medkits in the safe room, but in those cases there are at least four medkits scattered throughout that map.  I also like that map three uses dynamic pathing, which means you are forced to take a different path each time you play it.  As with all elevators that descend, zombie bodies act strange and sometimes hang in mid-air as the elevator goes down, making it look like they are floating up (actually they are stuck in one place, but you are moving down).  Hopefully we will soon see this map available on official dedicated servers.

Thank you Herbius for all of your efforts to bring this cool map to L4D2!