Allow the usage of DNSSec client verification

[phax]

See e.g. https://dnsinstitute.com/documentation/dnssec-guide/ch03s03.html

https://stackoverflow.com/questions/26701328/dnsjava-how-to-do-a-lookup-with-dnssec-validation

https://github.com/adamfisk/DNSSEC4J/blob/master/src/main/java/org/littleshoot/dnssec4j/DnsSec.java