* python_test: fix cython_examples in doc/ and tests/
* update setup.py to parse the bazel version string better
* all: centralize all python deps into stackable requirements files in python/
* format
* Move cython test into the proper package
* Add cross-reference dependency comments for requirements and setup.py
* re-enable version pinning on CI, fix formatting
* fix up torchvision version
* fix case in shell