Pin Pillow to latest and use a torchvision that works with it (#32290)
Summary:
Follow on from https://github.com/pytorch/pytorch/pull/31777, as suggested in https://github.com/pytorch/pytorch/pull/31777#issuecomment-575166543.
Pillow 7.0.0 removed `PILLOW_VERSION` and `__version__` should be used instead.
torchvision 0.5.0 switched from using `PILLOW_VERSION` to `__version__`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/32290
Differential Revision: D19430280
Pulled By: mrshenli
fbshipit-source-id: be8d6317a4948d71e818adeafe61dfe567df5601
