v0.6.0

• Feature / BC break: The Request and Response objects now follow strict
  stream semantics and their respective methods and events.
  (#116, #129, #133, #135, #136, #137, #138, #140, #141 by @legionth
  and #122, #123, #130, #131, #132, #142 by @clue)

  This implies that the Server now supports proper detection of the request
  message body stream, such as supporting decoding chunked transfer encoding,
  delimiting requests with an explicit Content-Length header
  and those with an empty request message body.

  These streaming semantics are compatible with previous Stream v0.5, future
  compatible with v0.5 and upcoming v0.6 versions and can be used like this:

  $http->on('request', function (Request $request, Response $response) {
      $contentLength = 0;
      $request->on('data', function ($data) use (&$contentLength) {
          $contentLength += strlen($data);
      });
  
      $request->on('end', function () use ($response, &$contentLength){
          $response->writeHead(200, array('Content-Type' => 'text/plain'));
          $response->end("The length of the submitted request body is: " . $contentLength);
      });
  
      // an error occured
      // e.g. on invalid chunked encoded data or an unexpected 'end' event 
      $request->on('error', function (\Exception $exception) use ($response, &$contentLength) {
          $response->writeHead(400, array('Content-Type' => 'text/plain'));
          $response->end("An error occured while reading at length: " . $contentLength);
      });
  });

  Similarly, the Request and Response now strictly follow the
  close() method and close event semantics.
  Closing the Request does not interrupt the underlying TCP/IP in
  order to allow still sending back a valid response message.
  Closing the Response does terminate the underlying TCP/IP
  connection in order to clean up resources.

  You should make sure to always attach a request event listener
  like above. The Server will not respond to an incoming HTTP
  request otherwise and keep the TCP/IP connection pending until the
  other side chooses to close the connection.

• Feature: Support HTTP/1.1 and HTTP/1.0 for Request and Response.
  (#124, #125, #126, #127, #128 by @clue and #139 by @legionth)

  The outgoing Response will automatically use the same HTTP version as the
  incoming Request message and will only apply HTTP/1.1 semantics if
  applicable. This includes that the Response will automatically attach a
  Date and Connection: close header if applicable.

  This implies that the Server now automatically responds with HTTP error
  messages for invalid requests (status 400) and those exceeding internal
  request header limits (status 431).