Diane 1.0.0 API documentation

Returns:
  [events-channel state-atom close-fn]
  - a channel onto which will be put Server Sent Events from the stream
    obtained by issuing a get request with clj-http to url with 
    custom-options
  - an atom representing the state of the client
  - and function with which to close the client

Sticks as close to http://www.w3.org/TR/2009/WD-eventsource-20091029/ as
makes sense on the server side.