WIP: Resolve "include PoTS lecture exercises into Cook Book"

What does this MR do?

Improve the Cook Book by filling it with more recent information and useful examples.

• Infiltration into homogeneous medium (PoTS Ex 2)

  Use Paraview: Load data, switch between variables, use Plot Over Line. Change parameterization by switching mapping.

• Evaporation from homogeneous medium

  Change boundary conditions. Understand error messages of DORiE. Analyze results.

• Infiltration into heterogeneous "checkerboard" medium.

  Write a mapping file. Analyze with Paraview: Use Glyph.

Is there something that needs to be double checked?

Can this MR be accepted?

• Pipeline passing
• Added entry to CHANGELOG.md

Related issues

Closes #9