Added ability to detect if a OWLEntity derived from a SKOS document.
Fetching and creating an OntologyTermValidationDescriptor, and fetching terms, in a kind of hacky way for now.

However, now allows a spreadsheet to be created with the concepts, which
behaves correctly and can be reloaded, and indicates the approach is
working.
Refactoring to allow ValidationType for Narrower and Directly narrower to be added, and terms fetched that way in line with OWL Terms
Correctly support Narrower for a deep recursive collection, with Directly Narrower just going one level deep
removed some warnings
Some refactoring, to unify how the label for a SKOSConcept is determined for display