AutoFill lobby slots

[KionX]

Adds the AutoFill feature slots lobby AI and their division into nth number of teams

[PhilipJFryFAF]

seems to work just fine - even supports AIs that are loaded via mods (eg. Uveso AI or Dilli)

[shalkya]

would it be possible to add a message on hover especially for the number of team. It isn't obvious at first glance.

[shalkya]

 `Teams Count`

How many teams should there be? (Players and AI will be split evenly between, will not work if the number of teams specified can't be divided into this number)

could you use this tooltip ? Is it too long ?
also can you make so when you can't divide (eg 8/3) then you it doesn't change or give a warning. I guess you can keep it like you did, but need to have a notification about that. Because putting 3 and getting 4 teams is weird.

[PhilipJFryFAF]

@KionX i'd like to merge your PR but i'd prefer having the suggested changes from @shalkya in if possible