Rewrite using pyviz and panel

[rsignell-usgs]

Instead of ipywidgets, try using pyviz instead.

[ocefpaf]

Pinging @philippjfr for awareness (or in case he wants to add something to his infinity list of tasks 😄).

@philippjfr we got @apkrelling to work on this project and she is almost done factoring out the code from the previous "GUI" we had. The next step is to start creating a Panel App for it. This would also be a nice example to display in the docs 😉

If you have any tips, suggestions, or want to review PRs let us know. Your input will be greatly appreciated!

[philippjfr]

This is great! Please ping me on the PR once it's up and I'll try to provide feedback.