GitLab

Summary:
- Deprecates data utils (with warning that will be removed in v0.12)
- replaces all usages of `torchaudio.datasets.utils.download_url` with `torch.hub.download_url_to_file`
- replaces all MD5 hashes with SHA256 hash

#Addresses https://github.com/pytorch/audio/issues/1883

Pull Request resolved: https://github.com/pytorch/audio/pull/2073

Reviewed By: mthrok

Differential Revision: D33241756

Pulled By: jdsgomes

fbshipit-source-id: 49388ec5965bfc91d9a1d8d0786eeafb2969f6cf