ConceptKeywords are not written to HydroDesktop database

jirikadlec2[CodePlex]
The HydroDesktop database has a table OntologyConcepts, but this table is empty. the Variables table has a ConceptID foreign key.

Expected behavior is: When a Variable is saved to the database, also save the OntologyConcept information of the variable.

note: This requires expanding HydroDesktop.Interfaces.ObjectModel.Variable by adding the ConceptKeyword property to Variable.

Start by tracing how HydroDesktop.Interfaces.ObjectModel.Variable is saved and how its ConceptID relates to the OntologyConcepts table. Check the requested ConceptKeyword property and the existing database persistence path. Done means saving a Variable also stores its ontology concept so OntologyConcepts is populated and the relationship is preserved.

Written by the indexing model from the issue text.