unable to communicate with localhost when setting up Kerberos-related tests

Nick Dimiduk gave an ask over on HBASE-23760 to change some of the Hadoop-level configuration properties around secure cluster setup from localhost to 127.0.0.1. He and Bharath Vissapragada have been chasing some issues with ZooKeeper and not having a resolution of localhost to 127.0.0.1.

Before I start making a change, how sure are we that this is an issue? Assuming that it's the nightlies that we see these on, how about we make a change to increase the krb5 and spnego debugging to see if we aren't resolving names properly?

There might be a debug property for DNS lookups in Java too.... maybe?