* Fix https://github.com/miekg/dns/issues/555 dnsutil.TrimDomainName tests fail
* Remove comment
* Clean up comments and code.
* Clean up comments, use dns.Fqdn() where we can, lint.
Use :0 for loopback testing. This is more portable between testing environments.
Add testRR that calls NewRR and throws error away - apply it everywhere where needed.
It seems only Go 1.9 can deal with :0 being used. Disable 1.8 in travis.
If sudo is not needed, Travis will run the builds in a faster containerized architecture.
Removed "-short", added "-race". Wall time loss seems reasonable.