Encoding of principle application to (meta)data

[markusstocker]

Some (sub) principles apply to metadata, data or both. This application is encoded with a suffix "-MD" or "-D" in URI fragments. However, for subprinciples that apply only to either metadata or data (e.g. F2) this suffix is omitted, leading to an exception in downstream processing.

Suggestion: Encode the application of the (sub) principle to metadata, data, or both as an additional property to instances of Metadata and Data classes (or similar).