Save Bibframe output to a triplestore

[rjyounes]

This could be ingested into a Vitro instance or automatically saved to the Vitro database.

Issues to consider:

• How to handle inconsistent Bibframe results when the Bibframe vocabulary or converter is updated
• How to handle multiple conversions of the same bibid
• Will need to dedupe URIs and apply other ld4l post-processing

[rjyounes]

Consider keeping files from each conversion, so that we can compare against a future conversion of the same bibid to see if there have been any changes. Since we're already writing the marcxml and some rdf - in the case of turtle format - to a file, change this to always write to file. Always write in rdfxml so comparisons can be made even if a different format has been selected.