Change rdf:type of INSPIRE Theme Register concepts from skos:ConceptScheme to skos:Concept

[arantzaetxebarria]

This issue comes from INSPIRE Registry helpdesk INSPIRE-MIF/helpdesk-registry#44
From: ODP-hil

In the INSPIRE Theme Register terms are typed as skos:ConceptScheme. For example:

  <dct:identifier rdf:datatype="http://www.w3.org/2000/01/rdf-schema#Literal">http://inspire.ec.europa.eu/theme/hy</dct:identifier>
  [...]
  <rdf:type rdf:resource="http://www.w3.org/2004/02/skos/core#ConceptScheme"/>
  <skos:inScheme rdf:resource="http://inspire.ec.europa.eu/theme"/>

I believe it would be more accurate to type the single concepts as skos:Concept while maintaining the rdf:type of the top level http://inspire.ec.europa.eu/theme as skos:ConceptScheme.