Webdav: fully implements the controller and response

The controller is tested from real request scraped from apache mod_dav implementation. The requests were scraped using a wireshark-like tool. Those requests have been adapted to suit to our xml.

src/Bundle/ChillDocStoreBundle/Dav/Response/DavResponse.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\DocStoreBundle\Dav\Response;
+
+use Symfony\Component\HttpFoundation\Response;
+
+class DavResponse extends Response
+{
+    public function __construct($content = '', int $status = 200, array $headers = [])
+    {
+        parent::__construct($content, $status, $headers);
+
+        $this->headers->add(['DAV' => '1']);
+    }
+}