(cherry picked from commit 8eab48aa)

It is now supported by the MATLAB editor (as of R2022a).

The old ASCII notation is left in some files that we copy as-is from other
sources (e.g. in the contrib/ and m4/ subdirectories).

The particles submodule is not updated at this point, because it is in an
inconsistent state.

[skip ci]

Closes issue #1679

[skip ci]

Also clarifies restructures section on optimal policy and clarifies calling order of commands

- remove trailing whitespace
- replace tabs with spaces as per PEP guidelines

Manually cherry-picked from 628c4cf2.