Add tutorials demonstrating projection center calibration functionality

[hakonanes]

Description of the change

This PR adds three new tutorials demonstrating various projection center (PC) calibration functionality:

• Extrapolate PCs from a mean to obtain a map of PCs
• Fit PCs from selected PCs to obtain a map of PCs
• Reproduce Ni example from Pang et al. (2020) (https://doi.org/10.1016/j.ultramic.2019.112876) to show sloppy orientation/PC optimization landscape. Our results using the Nelder-Mead algorithm reproduces theirs using the SNOBFIT global optimization algorithm.

Other notebooks are updated to use the new functionality.

Docs and tests are attempted to be excluded from the source distribution in this PR. This was tested using manifix. If this is actually the case is still uncertain, so at least one release candidate, 0.8.0rc1, will be made to ensure that they are indeed excluded.

Progress of the PR

• Docstrings for all functions
• Unit tests with pytest for all lines
• Clean code style by running black via pre-commit
• Remove documentation from distributed package, since it continues to increase in size. Solves Consider excluding docs and tests from package distribution #557.
• Update which notebooks to run every monday

Minimal example of the bug fix or new feature

See documentation built from this PR.

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.
• New contributors are added to release.py, .zenodo.json and
  .all-contributorsrc with the table regenerated.