Recompilable-gscs-for-BO2-zombies-and-multiplayer/Plutonium specific gsc-related fixes

Fixed gscs for Plutonium Only:

Zombies Announcer

Compile _zm_audio_announcer.gsc and place it in maps/mp/zombies.

This will fix the announcer not having any dialog on all maps and gamemodes.

Tombstone

Compile zm_transit_utility.gsc and place it in maps/mp.

This will allow tombstone to spawn in on dedicated servers.