[DO_NOT_MERGE] Stream support for k8s client request

Needed for https://github.com/openshift/origin/pull/136
@VojtechVitek I know but io.ReadCloser has io.Reader and io.Closer, but regarding the streaming we need just the io.Reader, which you can cast by specifying it in function return values `func (r *Request) Stream() (io.Reader, error)`.
This way only the io.Reader will be returned, not the whole io.ReadCloser