* Add anchor time to persistence schedule

Introduces a new public-setting persisted-model-refresh-anchor-time,
representing the time to begin the refresh job. Defaults to midnight
"00:00".

Also peg the cron jobs to run in the first of: reporting timezone, system timezone, or
UTC. This means that if a user needs the refresh to be anchored consistently to a certain time in a certain place, they need to update reporting timezone to match.

* Add tests for anchor time

* Force anchor-time to midnight if refresh hours is less than 6

* Need to check that hours was passed in

* Fix ns lint

* Add tests to ensure timezone is being set on trigger