Consider storing rank in the database

[UEWBot]

It's currently calculated when needed, but doesn't actually change very often (more frequently than score, because it can change due to other players' scores changing). Would be directly accessible to templates.
May be useful to add a rank_tied attribute, too, because that can be tricky to determine.

Would affect TournamentPlayer and maybe also RoundPlayer. Could also do GamePlayer, but there's no clear need.
It may also make sense to add GamePlayer.best_country_rank (and GamePlayer.best_country_tied?) or similar.