Include documentation, tests and auxiliary files in sdist

[mgorny]

Fixes #12

[kurtmckee]

Tested locally:

gh co 17
tox -e build

# Copy sdist filename
# In an isolated directory:

tar -xzf $SDIST_FILENAME
cd feedparser_sgmllib-2.0.0
tox p

git init
git status

The package built, tox ran without issue, and things look good!

I'd like to ask for your opinion, based on your experience: the sdist contains a file named PKG-INFO, which shows up in the git status output. Should this file be added to .gitignore?

I don't have experience in this area, so I'm hopeful you can speak to this. If it should be added, let's add it in this PR. If you know it should NOT be added, or you don't have an opinion for your use case, I'll come back to merge and then prep a new release.

[mgorny]

I'd like to ask for your opinion, based on your experience: the sdist contains a file named PKG-INFO, which shows up in the git status output. Should this file be added to .gitignore?

I don't think so. .gitignore only covers what's actually in the working directory of the git repository, and I don't think there's really any scenario when that file gets created in that working directory.

[mgorny]

Thanks!

[kurtmckee]

You're welcome, and thank you for contributing! ❤️

I just released v2.0.1. Let me know if you encounter any additional issues!