Move workflow-cli binaries to Azure Blob Storage

[sgoings]

1. Ensure we don't leave the GCS bucket orphaned and available for takeover like we did with the S3 --> GCS migration
2. Some parts of the README will need to be updated as well
3. Download/installer will need to be updated: http://deis.io/deis-cli/install-v2.sh

[Cryptophobia]

This issue was moved to teamhephy/workflow-cli#7