Discovery fails if computer name /etc/hosts

[mfikes]

See dmotz/natal/issues/21

@zilvinasu Indicated (see glosoli in http://irc.fikesfarm.com/log/clojurescript/2015-11-04.txt) that the extra entry had been added manually.

The question in my mind is whether this fundamentally affects mDNS, and if not, if Ambly is somehow mishandling the situation.