Make 1.0 release

[python]

Make 1.0 release

[JukkaL]

If I'm reading https://packaging.python.org/en/latest/guides/dropping-older-python-versions/ correctly, we should first upload a package that explicitly supports Python 2.7, and then we can drop it in a follow-up release (1.0). I'm going to make a 0.4.4 release first that only adds an explicit Python 2.7+ version requirement. It's probably not a big deal, but let's try to do this by the book.

[JukkaL]

0.4.4 is now out with an explicit Python version requirement: https://pypi.org/project/mypy-extensions/0.4.4/

[JukkaL]

I'm going to also upload a wheel for 1.0.0. Previously we've only uploaded a tarball, but having also a wheel seems like the right thing to do.

[JukkaL]

1.0.0 is out: https://pypi.org/project/mypy-extensions/1.0.0/