[MERGED PR] Disables antag captains on classic

[Arlian]

Mostly disagree with removing Captain's ability to roll antagonist. There should be a clear distinction between Captain and Security, and Captain being able to roll antagonist is one of the major factors that adds to that distinction. The PR seems to mostly be against how powerful the Captains kit is in general, so I could see a slight nerf to the Captains kit being more effective at accomplishing the goal without completely changing how the role works (and spawnkilling is against the rules anyway).