Communication protocols

SAREF4ENVI defines s4envi:usesCommunicationInterface and s4envi:usesCommmunicationProtocol, and s4envi:System, which from its definition read more like a CommunicatingSystem

Should decide on which modelling approach: SAREF4SYST if there's a clear need for describing the topology of the network. For SAREF4ENVI the network topology is not so relevant for the usecases.

See saref-portal#3