Add CrystalMap.plot(), use matplotlib-scalebar, add xmap notebook

[hakonanes]

Signed-off-by: Håkon Wiik Ånes hwaanes@gmail.com

Description of the change

This PR aims to make plotting a CrystalMap simpler.

• Add CrystalMap.plot() method (using orix.projections.CrystalMapPlot, similar to Vector3d.plot() and Miller.plot())
• Move CrystalMap notebook from orix-demos and improve it
• Use matplotlib-scalebar instead of directily using Matplotlib's AnchoredSizeBar. This enables us to remove lots of code, and brings easier customization of the scalebar.
• Add attributes scalebar and colorbar to CrystalMapPlot for easy access, which are None until add_scalebar() and add_colorbar(), respectively, are called.

Progress of the PR

• Docstrings for all functions
• Unit tests with pytest for all lines
• Clean code style by running black via pre-commit
• Finish notebook editing
• Finish testing of CrystalMap.plot()

Minimal example of the bug fix or new feature

This code

>>> xmap
Phase   Orientations                 Name  Space group  Point group  Proper point group       Color
    1   6043 (51.6%)      ferrite/ferrite         None          432                 432    tab:blue
    2   5657 (48.4%)  austenite/austenite         None          432                 432  tab:orange
Properties: iq, dp
Scan unit: um
>>> fig = xmap.plot(overlay="dp", remove_padding=True, return_figure=True)
>>> fig.savefig("/home/hakon/phase_map_dp.png", bbox_inches="tight", pad_inches=0)

produces this phase plot with dot product values in overlay

For reviewers

• The PR title is short, concise, and will make sense 1 year later.
• New functions are imported in corresponding __init__.py.
• New features, API changes, and deprecations are mentioned in the
  unreleased section in CHANGELOG.rst.

[hakonanes]

Note that most of the added lines (about 1,600) are from the notebook.

[hakonanes]

This is ready for review (the notebook can be viewed here: https://orix--185.org.readthedocs.build/en/185/crystal_map.html). There is no rush, but I would like for it to be part of v0.6.

[pc494]

This looks good at a glance, I'll add it to the chunk of stuff I do when I get back to #175, will easily make it into v0.6

[hakonanes]

The notebook has changed very little from the one in orix-demos (nbviewer link), apart from way simpler plotting. The most valuable feedback for me (although all feedback is appreciated!) would be on the CrystalMap.plot() method API, i.e. is it sufficiently customizable and behaves as expected.

[pc494]

I'm looking forward to putting this code through it's paces

[hakonanes]

Awesome, thanks a lot! Looking forward to using it myself, as it makes life much easier...