Argparse-manpage-birdtools

* Moved to bird tools opinion, NEWS section no longer maintained.

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* The "epilog" from argparse object is dumped to "COMMENTS" sections.

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* fixed testsuite for Python 3.9

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* drop additional .br tag from paragraphs so the multiline text is nicer

* provide argparse-manpage via entry_point

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* Fixed shebang in /bin/argparse-manpage script so it works on
Debian/Ubuntu as well as on Fedora.

* LICENSE file included in release tarball.

* Command-line executable now takes an optional '--output' argument.

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