Add MMC isotherm by Nfor 2010

[ronald-jaepel]

This PR adds the Mixed Mode Chromatography isotherm by Nfor et al 2010.

ToDos:

• [x] Implement Isotherm Flux
• [ ] Implement Isotherm Jacobian
  • [ ] First draft is implemented, but breaks atm, needs a second look
• [ ] Run tests (once jacobian is implemented)
• [ ] Documentation:
  • [x] Add Interface documentation
  • [x] Add model documentation
  • [ ] Link to the isotherm documentation pages at the correct sites
  • [ ] Test build and validate documentation

[ronald-jaepel]

cadet_MMC.zip Here's a windows binary of the current state. This is usable with .discretization.use_analytic_jacobian = 0