FilterInstruction must be Identifiable
Due to the move of Identifiable from disco-model to gesis-ddi-model, Identifiable has to be implemented as an interface.
FilterInstruction extended Identifiable. It would be nice to have a "IdentifiableImpl" that classes can extend from, so that subclasses don't need to implement all methods and properties. Also, this IdentifiableImpl should be an AbstractBaseEntity with an id.
Edited by Thirolf, Florian