DOI metadats mods

[JackS9]

• JIRA task: https://sdx-sdsc.atlassian.net/browse/PURR-117
• PURR core addition: 0 - DOI metadata mods
• Summary of Issue: When reviewing the metadata set that currently PURR datasets have, we find that more elements are necessary to be added to the metadata set, which is going to improve the interoperability of PURR metadata with other infrastructure, scripts, and tools that evaluate level of FAIRness of metadata that PURR provides.
• Summary of Fix/Changes: This change provides new data to Datacite from hubzero, data that we already have, but it's data they are providing datacite in a large XML metadata blob.
• Summary of Testing: Testing done by PURR staff on their dev environment. This will be tested again on PURR production hub by PURR staff.
• Hotfix needed? This will be pulled to PURR prod as part of testing and targeted for next CMS release (2.2.27)

[JackS9]

I'll make the changes and resubmit a new PR? I'll also share your comments with Jerry (the author of the code).

[JackS9]

Made changes recommended by Nick. I only added a TODO comment for the 'admin' issue with regard to rendering a tag cloud, pending contact with original author about the changes. Also, the changes for this PR can not be tested on my dev machine, so hopefully that can be done by PURR or somewhere with DOI-Datacite set up.

[nkissebe]

I made the changes I requested :)