Re-registers unpublished/archived/deleted editions

Editions which have been archived or unpublished in Whitehall don't have
their state updated in Panopticon.

Story: https://www.pivotaltracker.com/story/show/69528904

This adds the "unpublish" and "archive" verbs to the Panopticon
Registrar service listener and sets the adequate state on the
RegisterableEdition object sent to Panopticon.

This solution also requires updating `edition_test#should_remove_published_edition_from_search_index`
since this now triggers an external request.
Ideally, this end-to-end test would not be stubbing out the service listener as the real value in these tests is that the full stack is wired together correctly. There are test helpers available for stubbing and asserting the actual registration requests themselves in `GdsApi::TestHelpers::Panopticon`. See the `PanopticonRegisterArtefactWorkerTest` for an example of this in use.