- Testing, testing, testing

  Currently, this plugin always crashes when sending a response.
  It's probably a small fix, but the whole thing is *very* lightly
  tested.

- SPDY/4 protocol support

  If SPDY/4 ever gets any traction we should implement that. At this point,
  it's probably worth using a third-party SPDY marshalling library.

- Chunked encoding support

  Figure out what's neede to support origin servers sending chunked
  requests.

- SPDY client suport

  Is might be useful to support sending SPDY requests to origin
  servers. This would be necessary for push support, for example.
