Include Mathematica interface

[krikun-a]

We should add an example of the workflow where the equations are developed in Mathematica and then exported to the Python code. This would include:

• the Mathematica notebook with the equations, i.e. plain ionic lattices, DeTurck method.
• the Mathematica script, which transforms the given equations/BCs into the Python readable format.

[NicolasChagnet]

I have gathered and cleaned up a notebook for the Gubser-Rocha 1D lattice case. I left the output-to-python part of the code at the end but it should eventually be replaced with the universal module (work-in-progress) for pythonification. 1DLatticeSetupMathematicaFluctuations.zip