Fix reading of Oxford Instrument's *.ebsp files with format version 6

[hakonanes]

Description of the change

This PR fixes #690.

And #701.

Progress of the PR

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

Minimal example of the bug fix or new feature

The map (x, y) integer positions are new files with format version 6

>>> import kikuchipy as kp
>>> s = kp.load("file.ebsp")
>>> s.original_metadata
├── beam_x = array([-28.11170417, -26.11170417, -24.11170417, -22.11170417,
       -20.1117 ...    1.88829583,
         3.88829583,   5.88829583,   7.88829583,   9.88829583])
├── beam_y = array([34.11170417, 34.11170417, 34.11170417, 34.11170417, 34.11170417,
       ... 9583,
       -3.88829583, -3.88829583, -3.88829583, -3.88829583, -3.88829583])
├── file_order = array([  1,   0,   2,   4,   3,   6,   9,   5,   7,   8,  13,  10,  11,
       ...  386, 387, 388, 389,
       391, 390, 392, 393, 396, 394, 395, 397, 398, 399])
├── map1d_id = array([  0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,
       ...  386, 387, 388, 389,
       390, 391, 392, 393, 394, 395, 396, 397, 398, 399])
├── map_x = array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16,
    ... ,  6,  7,  8,  9, 10,
       11, 12, 13, 14, 15, 16, 17, 18, 19], dtype=int32)
└── map_y = array([ 0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
    ... , 19, 19, 19, 19, 19,
       19, 19, 19, 19, 19, 19, 19, 19, 19], dtype=int32)

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 kikuchipy/__init__.py and .zenodo.json.

[review-notebook-app]

Check out this pull request on 

See visual diffs & provide feedback on Jupyter Notebooks.

---

Powered by ReviewNB