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/Exception/ParseRequestException.php

@@ -0,0 +1,14 @@
+<?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\Exception;
+
+class ParseRequestException extends \UnexpectedValueException {}