Random special jobs on roundstart

[wivernshy]

Someone in the discord reminded me to post this here, so-

Basically just a "Random" option to select in job preferences, that would pull from the list of gimmick jobs you only see when latejoining.
You never know what you're gonna get! Would be great for people wanting more improv, and would give these jobs a chance to roll roundstart antag.

[aloe]

From a purely technical standpoint, this would probably need some special-casing in job selection code. Should be doable, though.