Make CereStation eligible for random map selection on 60+ players only

[dearmochi]

What Does This PR Do

• Adds min_players_random variable (default 0) to /datum/map. Used to filter out potential map picks during random map selection (that is, random map day) if the player count at the time of selection does not exceed it
• Sets the above variable to 60 for CereStation. I picked that number kind of randomly, so I'm open to adjusting it

Why It's Good For The Game

On random map days, any map can currently be picked which is fine for normal pop. The problem is when CereStation (a large map) is picked during off hours where departments are rarely filled. At the time of writing, I just saw it get picked and the round started with 12 players in-game. That's a ridiculously low number

This doesn't solve the voting issue, but it should alleviate some of the frustration of having to deal with that map with hardly anyone online

Testing

Outputted the list of possible map picks at 60 then 0

Changelog

🆑
tweak: CereStation may only be randomly picked if there are 60 players online or more on round end
/:cl:

[meow20]

literally solved world hunger in one pr

[Sirryan2002]

approved for code

[Danchi299]

everyone was saying "it won't work", "map is selected round end", "there is big players difference between last round and next round".
well it's better to at least try something

[S34NW]

Not perfect, but better than what we currently have