artifact_categories
Add categories in the pipeline, allow an artifact to have a category specified which allows it to be shown or hidden by default. Adapt the CLI tools to hide artifacts of the category that don't `show_by_default=True`.
Remove the only instance of underscores in the pipeline yaml from the use of `analysis_lists`. Substitute it with `analysis-list`.
Split the tests into two subdirectories: those that work in pure python and those that use the C++ bindings.
Giacomo Vercesi