WT projects have OA mandate if they started after 2015.
set the datasource prefix
integrated (hopefully) all required changes from dnet40
OpenAIRE mdbuilder basically does nothing if the record has already an oaf:entity (for claim of records already in OpenAIRE)
Do not generate a new objIdentifier if there is one, even if it is not in the dri namespace (for claims, see r47589 )
Let's forget the repositoryId
codebase used to migrate to java8 the production system