pypi improvements

[n2ygk]

Fixes #804

Description of the Change

• add long_description (README.rst) so it shows up nicely on pypi
• add 'tox -e install' as a reminder of how to 'twine upload' pending fixing github webhooks.

Checklist

• PR only contains one change (considered splitting up PR)
• unit-test added
• documentation updated
• CHANGELOG.md updated (only for user relevant changes)
• author name in AUTHORS

[coveralls]

Pull Request Test Coverage Report for Build 1319

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.768%

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Totals
Change from base Build 1317:	0.0%
Covered Lines:	1268
Relevant Lines:	1338

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 1319

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.768%

---

Totals
Change from base Build 1317:	0.0%
Covered Lines:	1268
Relevant Lines:	1338

---

💛 - Coveralls

[auvipy]

thanks!