fix client interface

Author: frostealth

src/contracts/Client.php

@@ -28,10 +28,11 @@ public function delete($filename);
 
     /**
      * @param string $filename
+     * @param string $version
      *
      * @return ResponseInterface
      */
-    public function get($filename);
+    public function get($filename, $version = '');
 
     /**
      * @param string $filename