Fix test suite issues affecting Travis images

Fix test suite issues affecting Travis images

In the utilities used by the dejagnu test suites, use
getaddrinfo()/getnameinfo() instead of
gethostbyname()/gethostbyaddr(), as the results can vary when the
local hostname appears in multiple lines in /etc/hosts.

In t_ccselect.py, don't cause an error if the canonicalized local
hostname is "localhost".  The tests will continue to run in this case,
as long as we don't try to create duplicate principals.

In sim_server.c, bind to the wildcard address instead of the resolved
local hostname, to resolve a mysterious problem observed in Travis
where the second of three sim_client send() operations fails with
ECONNREFUSED.