Windows: afslogon major refactoring NPLogonNotify()

Windows: afslogon major refactoring NPLogonNotify()

This is a major refactoring of NPLogonNotify() that is meant
to reduce redundancy and add functionality.  Key highlights
include:

 * New Domain\user hierarchy that permits configuration
   settings to be applied on a per user basis instead of a
   domain basis.  As part of the extension the username itself
   can be mapped.

 * Attempt to import the MSLSA credentials prior to performing
   KFW_AFS_get_cred().

 * Do not perform redundant KFW_AFS_get_cred() calls.

 * Add a flag to indicate if the authentication name is the
   LSA principal name.

 * Add more debugging messages.

Change-Id: Iacd6c6b4d3fe25f07a9c6982d0859eee22d09fe8
Reviewed-on: http://gerrit.openafs.org/7635
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>