Add rotation from path ends

[argerlt]

Description of the change

~~CURRENTLY A DRAFT! This is an almost direct copy of code from #558, and there are some comments that have not been addressed here about how type casting works. ~~

Update: done and ready for review.
@hakonanes, I ended up adding all your suggestions from #558. It matches better with the rest of ORIX.

I also added some notes about the definition of "shortest path", which is the issue I got hung up on in this comment.

Progress of the PR

• Docstrings for all functions
• Unit tests with pytest for all lines
• Clean code style by running black via pre-commit

Minimal example of the bug fix or new feature

Output from the included example:

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.
• Contributor(s) are listed correctly in __credits__ in orix/__init__.py and in
  .zenodo.json.

[argerlt]

Rebased this branch and fixed some formatting mistakes. Feel free to directly push any docstring or example edits as commits to my branch.

[hakonanes]

Looks good! I've made PR to your branch in argerlt#4.

[argerlt]

Done, and ready to merge.

Example is considerably better too, I will start splitting up my examples with formatted text between them in the future.