Switch to poetry

[licht1stein]

@phistrom I would like to switch the project to poetry and add automatic publishing of the master branch to PyPi using Github Actions, is it ok with you?

Also while we're at it, do you still need Python 2 support?

[phistrom]

1. What would be involved with switching to poetry? I'm afraid I'm unfamiliar. At a quick glance it appears to be a replacement for pip?
2. Automatic publishing to PyPI would be great. I am not familiar with Github Actions but willing to learn.
3. Does this project need Python 2 support? No. I've just always considered it a nice to have. Python 2 support has been easy to maintain so far (for me, anyway), but I would drop it if it ever became too annoying to do.

[licht1stein]

I'll prepare a PR. In order to publish automatically you just need to add your username and password to the repository secrets. I'll be able to use them in CI, but won't be able to see them.

[licht1stein]

This is a good read: https://snarky.ca/what-the-heck-is-pyproject-toml/