Add improve and generate documentation

[HannoSpreeuw]

The documentation has not been completed yet.
Still we want to merge this branch with main now.

The reason is that this branch was created off main recently, i.e. after the merge with the Use_solve_ivp_without_py-pde_wrapper branch.
After the merge we do not arrive at exactly the same oscillations as before the merge; the time of onset of the oscillations is the same, but e.g. the amplitudes differ.

An important aspect of our upcoming publication is the runs that were performed last August, i.e. prior to the merge.

For that reason I have created a release_v1.0.0 branch from commit 3cd8233, i.e. prior to merge.
This Add_improve_and_generate_documentation branch will be merged both here, i.e. with current main and with that release_v1.0.0 branch.

The documentation will be expanded on the release_v1.0.0 branch because it is targeting the release; i.e. scientists that want to reproduce our published results will be using the 1.0.0 release and the documentation should support them in doing so.