Add bots and nobots votes, set default bot skill to 8 (from 1)

Also set skill to the value votable servers use (they're still really bad, just not totally incompetent, if players feel intimidated by them they should play the campaign).

Now that there is a way to remove them for players, do we want bots on by default?

Should i also add them to rcon_restricted_commands? Idk how that works.