Not support for persistent connection

Force a connection close to be compliant with HTTP 1.1 (socket client does not support persistent connection at the moment)

Author: joelwurtz

src/SocketHttpClient.php

@@ -47,8 +47,9 @@ public function __construct(MessageFactory $messageFactory, array $config = [])
      */
     public function sendRequest(RequestInterface $request)
     {
-        $remote = $this->config['remote_socket'];
-        $useSsl = $this->config['ssl'];
+        $remote  = $this->config['remote_socket'];
+        $useSsl  = $this->config['ssl'];
+        $request = $request->withHeader('Connection', 'close');
 
         if (null === $remote) {
             $remote = $this->determineRemoteFromRequest($request);