Fixes power draw not being processed if no power was available

Should address some of the issues raised in Pull Request #6080
Fixes APCs drawing more power than they can to use to charge
Adds simple load balancing
Fixes fore solars control room area

Also changes solar area requires_power and always_unpowered to match
area/space
Merge remote-tracking branch 'upstream/dev-freeze' into power-net
Merge remote-tracking branch 'upstream/dev-freeze' into power-net
Merge pull request #6104 from mwerezak/power-net

Fixes for APCs (from dev), fix for solars area, and simple APC load balancing