knoten has a jupyter dependency - should it really?

[jlaura]

When creating a knotted environment, the library has a jupyter dependency. I get that the package contains notebooks, but not all users are going to want to have an arguably bloated environment that in includes the full jupyter installation.

For many, have jupyter installed in a base env and then registering the knoten kernel is the preferred workflow. Should jupyter be removed from the environment.yml because it is not a necessary component of the library? I am happy to PR in the change and include instructions in a README for how better to handle the visualizations / interactions through multiple environments.