Changes to XSL for DOI registration
Additions to workflow to support registration of blacked out items

Added a step registerPendingPublicationStep before pendingPublicationStep and an action RegisterPendingPublicationAction that registers the DOI.
This way, the path through the workflow determines how to register the DOI.
Instead of checking database for a specific state, now adding provenance metadata to indicate blackout was entered.
This provenance metadata is used to determine the target and metadata to register the DOI with.
Avoid checking for blackout if item is archived
Activate publication blackout for dryad test journal
Refactoring of Minter.register

Use EZID's API to determine if a DOI is registered, rather than relying on dx.doi.org
This eliminiates multiple bugs/confusing issues found in the previous implementation:

1. The implementation checked for a redirect response code (303), but the HttpURLConnection was configured to automatically follow redirects, so this code was not returned
2. DOIs registered with the test mode prefix were case-sensitive when checking with dx.doi.org
3. Unregistered test mode DOIs always redirect to a test mode page on datacite.org, so the redirect alone does not indicate whether or not the DOI has been registered
4. DOIs registered with EZID aren't immediately propagated to dx.doi.org
Updated publication blackout tests to only check last provenance
CDLDataCiteService utility methods to use with lookup
Expose CDLDataCiteService utility methods

For post-approval, to check the status of an item's DOI registered with
EZID
Rework status box after approving an item

Now a table that includes the DOI registration status from EZID