Merge pull request #839 from tianyiw2013/patch-1

Update annotation: TcpConnection->$context

src/Connection/TcpConnection.php

@@ -161,7 +161,7 @@ class TcpConnection extends ConnectionInterface implements \JsonSerializable
     /**
      * Context.
      *
-     * @var array
+     * @var object|null
      */
     public $context = null;