add additional levels of ents (auth and unauth) to the insecure delegation ent test
fix for errata 3441 of RFC5155
workaround for ldns-verify-zone nsec3 bug in regression tests
limit mode 0 closest provable encloser to optout
Merge pull request #1308 from mind04/2ent-optout

fix for errata 3441 of RFC5155