Add CVE-2014-4971 BthPan local privilege escalation

Add CVE-2014-4971 BthPan local privilege escalation for Windows XP SP3.

This module incorporates the feedback we have gotten so far on pull request 3534 for a different module; if there is more, we will update this code accordingly as well.
Thanks @stalepacket , but I'd like to know that this is actually the intent of @KoreLogicSecurity . It smells like refactor-rot, but just wanted to be sure the method isn't missing anything important.