Make `putStream` work with streams2. Fixes #156.

- Streams given to Knox are no longer kicked into "old mode," since Knox no longer adds `"data"` listeners.
- New stream-counter package is used for getting progress events without adding `"data"` listeners.
- Streams from Knox no longer start out kicked into "old mode," since Knox no longer calls `response.resume()` immediately. (This reverts 4836dbb6d07424a5d2058aabe24cee5f8167dff2.)