Fix object deletion response status

S3 returns 204 No Content instead of 200 Success status.

src/main/java/ninja/S3Dispatcher.java

@@ -645,7 +645,7 @@ private void deleteObject(final WebContext webContext, final Bucket bucket, fina
         StoredObject object = bucket.getObject(id);
         object.delete();
 
-        webContext.respondWith().status(HttpResponseStatus.OK);
+        webContext.respondWith().status(HttpResponseStatus.NO_CONTENT);
         signalObjectSuccess(webContext);
     }