Import new snapshot of gss-sample.c

As of 7e85c3da6385651515b7eca4ba7e7d7546e0b3f3.
Add authz checks, remove needless memsets, and don't mention
the (rare) potential of GSS resources being nonlocal to the
current process.
Make draft-ietf-kitten-gss-loop-01
Edits in response to Nico's comments
Edits in response to Greg's comments
Import new snapshot of gss-sample.c

As of 46c4cd30b9d06e5560dd876c41b1fdfe52f9aa98.
Incorporate Greg's edits, making check_authz() take just a name
and not a pointer to a name, and some whitespace tweaks.
Make draft-ietf-kitten-gss-loop-02