v1.4.0

• Feature: Improve error reporting for failed connection attempts and improve
  cancellation forwarding during proxy connection setup.
  (#23 and #26 by @clue)

  All error messages now always contain a reference to the remote URI to give
  more details which connection actually failed and the reason for this error.
  Similarly, any underlying connection issues to the proxy server will now be
  reported as part of the previous exception.

  For most common use cases this means that simply reporting the Exception
  message should give the most relevant details for any connection issues:

  $promise = $proxy->connect('tcp://example.com:80');
  $promise->then(function (ConnectionInterface $conn) use ($loop) {
      // …
  }, function (Exception $e) {
      echo $e->getMessage();
  });

• Feature: Add support for custom HTTP request headers.
  (#25 by @valga and @clue)

  // new: now supports custom HTTP request headers
  $proxy = new ProxyConnector('127.0.0.1:8080', $connector, array(
      'Proxy-Authorization' => 'Bearer abc123',
      'User-Agent' => 'ReactPHP'
  ));

• Fix: Fix connecting to IPv6 destination hosts.
  (#22 by @clue)

• Link to clue/reactphp-buzz for HTTP requests and update project homepage.
  (#21 and #24 by @clue)