MAGETWO-36075: Move dev/tools/Magento/Tools/I18n/pack.php

- added doc block

dev/tests/integration/testsuite/Magento/Setup/Console/Command/I18nPackCommandTest.php

@@ -67,6 +67,12 @@ class I18nPackCommandTest extends \PHPUnit_Framework_TestCase
         );
     }
 
+    /**
+     * Removes directories recursively
+     *
+     * @param string $dir
+     * @return void
+     */
     private function recursiveRmdir($dir)
     {
         if (is_dir($dir)) {