Reward positive votes

[Vayel]

Positive votes are essential to make sure that a comment is helpful, but the reputation system doesn't prompt us to vote for other comments. It's tricky to do if we want to avoid having users who collect reputation just by upvoting every comment, but perhaps we can find something.

[Betree]

That's really tricky, but I get the point of encouraging participation.

One way we could do that would be to limit reputation gains for positive votes specifically to something low (10pts per day?). That would introduce some complexity in the code.