Normalize space of metadata identifier path as it is done in "normal" mdBuilder
set the datasource prefix
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