Revert "Add pyproject.toml."
Revert "Add pyproject.toml."

This reverts commit 30421d6e807cb1597cfdc0405c2094c60439be30. I think
this causes the README render failure in `twine check` but I'm not sure
since I can't reproduce it locally. The clue I'm going by is the other
error about missing long_description_content_type.

adarnimrod/template,adarnimrod/template