I came across one of the utility to clean empty workflow folders (remaining after OOTB workflow purge) in http://aemfaq.blogspot.com/2013/07/utility-to-get-rid-of-folders-not.html. This utility is working in AEM 5.6 but not working in AEM 6.1 since AEM creates internal folders under instances node such as server0, 1, etc. Please let me know if there are any OOTB or Adobe recommended approach for cleaning empty workflow folders for AEM 6.1.