Clean metadata and user paths in notebook outputs

[bdice]

This is an update to #22 that strips unnecessary metadata and user paths from the notebooks. I have added pre-commit hooks and a helper script .render_all_notebooks.sh to assist with rendering and cleaning the notebooks.

Warning: I rendered these notebooks with development versions of signac and signac-flow to fix some bugs that caused warnings in the notebook outputs! The PRs fixing these issues are:

• https://github.com/glotzerlab/signac/pull/498 (merged, available on master branch of signac)
• https://github.com/glotzerlab/signac-flow/pull/460 (not yet merged to signac-flow)

[review-notebook-app[bot]]

Check out this pull request on 

See visual diffs & provide feedback on Jupyter Notebooks.

---

Powered by ReviewNB

[mikemhenry]

So do we only need to merge this one and not #22 ?

[bdice]

@mikemhenry This merges into #22, I just wanted to separate my changes since it was somewhat experimental.

[mikemhenry]

:man_facepalming: That's what I get for not reading