SDK doesn't provide standard Readable / Writeable stream interfaces

[Marak]

The current sdk has no way accepting standard readable streams for uploading, or writeable streams for downloading.

This is too bad, because project dependency superagent already supports this interface for HTTP.

see: https://visionmedia.github.io/superagent/#piping-data

Background information:

https://github.com/substack/stream-handbook
http://nodestreams.com/