Unbound 1.6.1 has a few bug fixes for resource leaks,
configuration robustness, compile environment interaction,
and maintaining the trust anchor. The 2017 trust anchor
(DS) is built into unbound and unbound-anchor.

File /etc/unbound/root.key holds 2010/2017 DS record until 2018
https://www.icann.org/resources/pages/ksk-rollover
https://www.iana.org/domains/root

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>