GETCONF doesn't resolve "auto" settings

Right now tor doesn't resolve auto settings when reporting them via GETCONF. This means the controller might need to know beforehand how tor will behave for any given auto setting, which might change across tor versions or even across consensuses. We should have a way to resolve auto settings so controllers can discover what setting tor will actually use.

Implementing this could be a lot of work because I think the behavior of many auto values gets determined by code in the relevant subsystem rather than in a centralized place like control.c.