A shareable generic datamode

Current data component datamodes explicitly define the variables in streams and to advertise, possibly adding calculation of variables, unit checking, etc.

Some users are capable/interested in arranging the input data themselves (through their own workflows/formulas/...) and less interested in touching CDEPS source code.

A "generic" datamode could pass the stream configuration into NUOPC states, copying the variables from file with specifiable names as user wishes largely trusting user inputs as provided.

With the user input variable data and names, data components can share such a component-agnostic generic datamode.