Structures for KB2871997

At the moment Kiwi extension crashes meterpreter when run against a patched system (so would mimikatz before this: https://github.com/gentilkiwi/mimikatz/commit/8d83d5ab93396263b8c8be8401381b02868fdad6 ). This is an attempt to port those changes over.

Hopefully @OJ will assist in vetting.