Block or warn when joining non ELO games

[xaxazak]

I keep beating good people and looking forward to moving up, only to find it's not ranked.
I'm not complaining about people wanting to play unranked games, but it'd be nice if I didn't have to remember to check the setup every time.

Suggestion: Have a profile option for non-ELO games, with four states:
- allow non ELO games
- warn when joining non ELO games
- block joining non ELO games
- block seeing non ELO games

I'd use #3.