feat: python 3.11 support; drop 3.6 and 3.7.

Fixed issue related to installation hangs on Windows with cython nthr…

…eads>=1.

Dropped python 3.5 and below.

Updated package dependencies.

Reformatted code per updates in black style.

Eliminated beta status classifier.

Fixed version update

Fixed author email.

Excluded __init__ module from cythonize and use 2 threads.