Add code paths to fully support PRIVATEDNS and PRIVATEOID keys.
PRIVATEDNS and PRIVATEOID require that alogorithm's name/oid also be checked along with its number 253/254. We left the implementation until there was an actual PRIVATEDNS or PRIVATEOID requested / specified. There are moves in DNSOP to allocate a set of test algorithm which will effectively burn each test algorithm number used for testing as you can't do proper cleanups at scale.
Add code and tests using example.com and ISC's OID (1.3.6.1.4.1.2495) to prevent collisions to demonstrate that PRIVATEDNS and PRIVATEOID can be used.