Add DataCite-accepted identifiers

[fenekku]

Here are the identifiers that could be added to the identifier schema in InvenioRDM (inveniosoftware/rfcs#11) mostly because DataCite accepts them. It would be nice to have them supported in the module.

• igsn (International Geo Sample Number) Their syntax is described here: http://igsn.github.io/syntax/ .
• lissn perhaps just redirect to issn
• w3id . Syntax seems very loose
• upc . Perhaps superseded by ean13 anyway
• eissn Perhaps just redirect to issn
• bibcode Syntax
• ror Research Organization Registry: https://ror.org/facts/
• Software Heritage Identifier: https://docs.softwareheritage.org/devel/swh-model/persistent-identifiers.html

[lnielsen]

bibcode already exists as ads (should probably be renamed though)

[lnielsen]

Another identifier is the Software Heritage identifier.

[tmorrell]

In 4.6 there is now RRID https://datacite-metadata-schema.readthedocs.io/en/4.6/appendices/appendix-1/relatedIdentifierType/#rrid and CSTR https://datacite-metadata-schema.readthedocs.io/en/4.6/appendices/appendix-1/relatedIdentifierType/#cstr