added raw format in order to return unformated guzzle response (#349)

src/Omniphx/Forrest/Client.php

@@ -245,6 +245,11 @@ private function handleRequest()
             $this->assignExceptions($ex);
         }
 
+        // If the format is raw, return the response as is
+        if($this->options['format'] == 'raw') {
+            return $response;
+        }
+
         $formattedResponse = $this->formatter->formatResponse($response);
 
         $this->event->fire('forrest.response', [$formattedResponse]);