Merge pull request opencv#579 from asenyaev/asen/fix_pylin_and_pycharm

Added lines for a proper work using pylint and an autocomplete in IDE

Merge pull request opencv#584 from asenyaev/asen/upgrade_3.4_again

Update 3.4 branch to the latest changes in master

Merge pull request opencv#568 from asenyaev/asen/remove_extra_modules…

…_3.4

Removed unused modules for 3.4 branch

Merge pull request opencv#561 from andruekonst/patch-1

Fix typo in Readme

Merge pull request opencv#500 from williamjacksn/upload-sdist-to-pypi

Include software distributions when uploading to PyPI

Merge pull request opencv#512 from asenyaev/3.4

Update 3.4 with master changes

Merge pull request opencv#483 from asenyaev/asen/arm_build

Add arm build to GitHub Actions

Merge remote-tracking branch 'upstream/master' into 3.4

Fixed if condition for release job (opencv#478)

* Fixed if condition for release job

* Added the test release job, changed if condition

* Merged all upload steps into one for pre-release

Merge pull request opencv#480 from opencv/master

Update build process & sync master and 3.4