Handling carryovers

I'm not merging this one because I definitely want @puls to review it.
That sort of seems reasonable, but the issue is that (at least right now), a game takes place in a round which is part of a phase. What you're suggesting would basically put rounds all over the place, right?

I think it's a benefit of my solution that every match definitely has a "main phase" — the one in which it actually took place — in addition to possible additional phases. Both for simplicity and nat…naturality? Is that a word?