Be lenient when a NSEC NameError response with RCODE=NXDOMAIN is received. This is okay according 4035, but not after revising existence in 4592.  NSEC empty non-terminals exist and thus the RCODE should have been NOERROR.
Be lenient when a NSEC NameError response with RCODE=NXDOMAIN is received.
This is okay according 4035, but not after revising existence in 4592. 
NSEC empty non-terminals exist and thus the RCODE should have been NOERROR.

If this occurs, and the RRsets are secure, we set the RCODE to NOERROR and
the security status of the reponse is also considered secure.



git-svn-id: 5ac9340a55e2f27e0b201b4c317755fd16d51776@3089 be551aaa-1e26-0410-a405-d3ace91eadb9

thozza/unbound,thozza/unbound,lucab/unbound,thozza/unbound,Karm/unbound,thozza/unbound,lucab/unbound,Karm/unbound,lucab/unbound,thozza/unbound,fastly/unbound,fastly/unbound,lucab/unbound,Karm/unbound,fastly/unbound,lucab/unbound,fastly/unbound,Karm/unbound