Change namespace

Author: RezaSR

ButtonDropdownSorter.php

@@ -3,7 +3,7 @@
  * @see http://www.yiiframework.com/doc-2.0/yii-widgets-linksorter.html
  */
 
-namespace app\components;
+namespace rsr\yii2;
 
 use yii\base\InvalidConfigException;
 use yii\base\Widget;