Move timing-related authority options into dirauth module
We should concentrate all of the options related to vote timing into the dirauth module.
Some of these will turn out to belong in voting_schedule.c: we'll need to be careful.
The ones I know of are:
- TestingV3AuthInitialDistDelay
- TestingV3AuthInitialVoteDelay
- TestingV3AuthInitialVotingInterval
- TestingV3AuthVotingStartOffset
- V3AuthDistDelay
- V3AuthNIntervalsValid
- V3AuthVoteDelay
- V3AuthVotingInterval