create a Jupyter notebook for each Hellweg example case

[bruhwiler]

The jupyter notebook(s) for each example should be placed in the corresponding examples/ subdirectory.

In the process, document the example clearly and create (in the first few code blocks) any necessary switches.

Also, in the process, clean up the examples so that they run relatively quickly.

Consider whether examples are partially duplicative or whether there are other important Hellweg features that merit a new example.

Each notebook should be tested with the main branch only.

[bruhwiler]

This effort was not completed. Closing issue because funding is no longer available.