Support deprecated/removed/replaced terms

[ddeboer]

We have the terminology source requirement to preserve outdated terms but no implementation yet to support that.

If we can agree on a way to have deprecated terms be marked in the sources (either by the source administrators or by us in our queries), we can include the status in the NoT API responses, and optionally the demonstrator.

In the terminology sources

Skosmos models this case as:

ex:old a skos:Concept ;
  owl:deprecated true ;
  skos:prefLabel "Old concept that has been replaced by a new concept"@en ;
  dct:isReplacedBy ex:new .

@rschalkrce suggested adding:

ex:old a skos:Concept ;
  skos:changeNote "Reason why the term was deprecated." ;

Other/better ideas to model this?

In our GraphQL API

A proposal (where reason could be derived from changeNote):

Term {
  ...
  deprecated {
    reason: String
    replacedBy: [RelatedTerm]
  }
}