(Survival): Fixed issue where the Survivors spawned at the incorrect area in The Passing Map 1 (Riverbank)

Fixed issue on Passing Map 1 where the L4D1 bots would spawn at random areas upon restarts

- Removed VSLib files and all VSLib related dependencies.
- Made it so the real Zoey spawns on L4D2 Survivor maps instead of "Fake Zoey".
- Co-op/Realism: Fixed issue on The Passing Map 3 where the game would crash when restarting the map.
- Fixed an issue when an extra Survivor died on the previous map, their health would be set to 1 instead of 50 if the round restarts.

We think we've finally found out why the United We Stand mutations are crashing.
It seems to be caused by not setting an "Image" for each Mutation's mode file.
From testing it should be fixed.
After we added the image key, we weren't getting any crashes.

Fixed extra bots not properly retaining their weapons and stats across map transitions.
In L4D1 campaigns, the extra L4D2 bots can now be revived with a defibrillator.

corrected all game modes (coop, realism, survival)

added support for realism mode

Normalized version directly from the Mutation Mod creator/author himself.
This version simply only adds the original survivors alongside the Left 4 Dead 2 survivors.
Everything else remains vanilla with no other changes such as special infected spawns.
So if you still want a harder difficulty challenge, you could still play on advanced or expert modes.