Improve the definition of the cfResProd entity

[jdvorak001]

We start with:

In CERIF, the concept of product is physially (cfResProd) and logically (cfResultProduct) defined as an entity in the ERM, represented by attributes and through maintaining relationships with other entities: classifications, fundings, products, projects, organisations, persons, facilities, equipments, services, media, indicators, measurements.

The entity product in CERIF has often caused confusion, it was maybe not stressed enough, that a CERIF product is considered a result in general, achieved through some effort - and not at all is it a commercial or physical product only. It was intended to also represent i.e. software or 'research data'.