Support streaming content down

[rgaudin]

We currently mostly use the high level transfer methods from boto3 to download content which only offers to download whole content into memory or filesystem.

It would be very handy to expose a streaming method that would iterate to fetch the data.

This would be done leveraging the Range options of get_object().

Note from the doc: Amazon S3 doesn't support retrieving multiple ranges of data per GET request.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.