Funnels working properly at last?

The fast majority of this is nonymous' code, but there were a few nagging bugs and some unclear code I addressed.
The really big one is that weather advancement has been broken for a REALLY long time, meaning that it was always one weather span further in the future than it was supposed to be.  Over long periods of time, this would result in correct behavior, but the funnels would always be accumulating water from past weather.  I suspect the weather radio was always one span behind as well, but none of these systems give out enough information to see this stuff happening unless you attach a debugger or something.
The main outstanding issue is that if you pick up a bottle, wander off and do stuff with it, then go back and drop it under a funnel, it will retroactively accumulate water from any intervening weather spans.

The solution for this is to only process more than one turn at a time when you load the funnel onto the map, but I don't have the energy to do that right now, and I want to get this landed, assuming I haven't missed something else.