issue2551253 - Modify password PBKDF2 method to use SHA512 Implement new PBKDF2-SHA512 more secure password hash function. Intended to be future default once I get more feedback. upgrading.txt: added doc for using it now. reference.py: Added enabling future features to use case for interfaces.py. admin.py: Changed perftest password command to use the default password function. Can be used to verify that new hash is enabled properly.