Update 3.4 branch with latest updates in master

Updated dependencies to the latest releases (openssl and ffmpeg) in a dockerfile, turned on building libpng

Updated submodules to 3.4.17 release

Update 3.4 branch after commits in master

Changed a path to config-X.py file after python limited API support, optimized uploading and downloading artifacts

The last run was a year ago.  https://ci.appveyor.com/project/skvark/opencv-python/history

This allows correctly resolving the numpy version requirement via PyPI metadata, using the same metadata regardless of what version of Python the package was built with or which wheel is uploaded to PyPI first.

Update 3.4 branch to the latest changes in master

Removed unused modules for 3.4 branch

Updated 3.4 branch to 3.4.16 release and added changes from master branch

Fix typo in Readme

"Programming Language :: Python :: 3.10",

Updated submodules to the release 4.5.4 and added python loader support