Example Usage: Narrative examples to guide new users

[hayesall]

The nnde_demos repository has good notes, but their presentation makes them difficult to follow.

Recommendation: Include Sphinx documentation or Jupyter notebooks to show steps of the computation alongside the narration for what occurs.

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sphinx documentation with the sphinx-gallery plugin is one option, or Jupyter notebooks can usually be rendered on GitHub.

For a real-world example of the sphinx-gallery approach, here is a web page that is generated from a markdown document

[elwinter]

I added a Jupyter notebook (tutorial.ipynb) to the nnde_demos repository (https://github.com/elwinter/nnde_demos) that walks the user through the process of solving a 1st-order ODE IVP using the nnde ppackage and examining the resulting network and the solutions it generates.