For various reasons, an operator might want to use specifics nameservers
instead of the systems ones to resolve CNAME in cname_lookup. This patch
creates a new configuration variable nameservers which accepts a list of
nameservers separated by commas. If not specified or empty, systems
namservers are used as previously.
Co-Authored-By: Tim Burke <tim.burke@gmail.com>
Change-Id: I34219e6ab7e45678c1a80ff76a1ac0730c64ddde
420e73fabd