Migrate from pipenv to poetry

[yukinarit]

Poetry seems be faster and easier to use.

[alexmisk]

Hey! If this ticket is not very urgent, can I take it instead of you? :-)

[yukinarit]

That is very helpful. Thanks! :)

[alexmisk]

Hey! Just want you to know I am working on the migration right now but stuck with the PyPI publishing.

For unknown reason Poetry includes dev dependencies defined in [tool.poetry.dev-dependencies] section in the list of global dependencies. It results in installing a huge list of unnecessary packages on pip install pyserde.

Also the support of installing extra packages from PyPI with Poetry builds (i. e. pip install pyserde[toml]) is tricky.

I hope I can manage these issues in a week or so. Cheers :-)

[yukinarit]

Thanks for the update! Can you please push to GitHub? I would like to take a look.