HTTP Stream Channels

I'd like for these to replace the rest-json1 channels:

 * Makes HTTP parseable as strings, takes care of Content-Length, chunked encoding, and all the binaryness of the protocol.
 * More general than JSON specific REST code we have now.
 * Usable against WBEM, Kubernetes, Docker, and maybe others.

Won't have keep alive or support non-UTF8 charsets in in this initial version. But that can be added later.