Multiphase/ Component specific Dispersion tensors

Feature request

Complex Dispersion tensors

What does this feature / why does DuMux need it:

Currently there are dispersion fluxes implemented for compositional-flow(1pnc) and tracer models. The dispersion tensors are either user defined, or defined using the scheidegger dispersion relation, which is velocity dependent.

Other dispersion tensors exist, and can be component specific or dependent on state and phase conditions. These dipsersion tensors could be added to make the dispersion interface useable in complex cases.