NEWS: prepare release notes for 4.0.2

pyproject.toml: switch from setup.py

We still use setuptools, but drop setup.py in favor of pyproject.toml.

Organize linter, docs and test dependencies as optional dependencies and
update GH actions accordingly.

Fixes #379.

NEWS.md: document CI changes

Also update the to-be version to 4.0.0, the next one is gonna be a new
major release.

Merge pull request #275 from grazzolini/fix-shlex-typo

afew/filters/FolderNameFilter.py: Fix typo on shlex call

release afew 3.0.0

release afew 2.0.0

Merge pull request #170 from aidecoe/dkim-validity-filter

Add filter verifing DKIM signature

fix #158

gitignore /.eggs

Codename teythoon