Order Fatality Notices by first published date

Order the Fatality Notices by first published date instead of last
updated date. Change the test to ensure order remains when a Fatality
Notice is updated.
Simplify Publishing API tests
Wire in an archive notice for archived editions

When an edition is archived, it gets republished to the content store with an
additional archive notice in the details hash.
Change first published and updated dates

Change first published and updated dates so these are realistic
Data migration to republish archived case studies
Merge pull request #1884 from alphagov/order-fatality-notices-by-first-published-date

Order Fatality Notices by first published date
PublishingApiWorker handles deleted models

Instead of raising an exception and retrying the job for the next 25 days, the
worker should end gracefully if the model does not exist for whatever reason.
Merge pull request #1889 from alphagov/publishing-api-archiving

Publishing api archiving
Merge pull request #1890 from alphagov/handle-deleted-stuff

PublishingApiWorker handles deleted models