Support for Python 3.11

[Hnasar]

Python 3.11 is set to release in 2-3 weeks, but wheels (or sdists) are unavailable for windows-curses.

Here's the docs on porting to 3.11 https://docs.python.org/3.11/whatsnew/3.11.html#id6

The release date is on 2022-10-03 but rc builds are already available.

We strongly encourage maintainers of third-party Python projects to prepare their projects for 3.11 compatibilities during this phase

https://www.python.org/downloads/release/python-3110rc1/

(Btw, it could be nice to be explicit in setup.py about which versions are supported https://peps.python.org/pep-0345/#requires-python )

        python_requires='>=3.6,<3.11',  # or <3.12 once 3.11 is supported

Thank you!