Fixes for DOI Registration, proper metadata, and registering blackout items

Trello 28: https://trello.com/c/eYNzIhHl

- Includes proper metadata document for registration (DataCite 2.2)
- Support for registering items in publication blackout, which has changed how publication blackout is recorded on an item in the database.  This is done by adding provenance metadata to indicate when the item entered publication blackout.
- The code that registers DOIs checks for this provenance, so __We will need to update metadata on blacked out items before deploying this__