Templatemail

- Just security dependency update, plus using Poetry and a modern CI

**Full Changelog**: https://github.com/kkinder/templatemail/compare/0.2.0...v1.0.1

This version adds some [MkDocs](https://www.mkdocs.org/) pages hosted on Read The Docs, as well as experimental SMTP support.

* Bumps urllib3 version in lockfile for CVE-2019-11324
* Fixes `standard_css.html` inclusion example.