disable blob and nuke on lowpop

[NateTheSquid]

not very fun to play when there's 5-10 people on

disable all antags when the crew is leds than 5-10 people imo. then if more people join make late joining antags more common for the rest of the round. far too many people rampage on lowpop and it discourages the already low amount of people from playing again, so its even more lowpop