MQTT non-informative connections behavior

[dsalychev]

This is not a standard issue, just information issue.

I try to setup future-based and callback-based MQTT connections at a BeagleBone and Angstrom Linux and catch an interesting situation:

• future-based connection drop after timeout expires (and print stack trace only about TimeoutException)
• callback connection drop with exception: java.net.UnknownHostException: beaglebone: beaglebone: Name or service not known

My /etc/hosts file hasn't been refactored to the "beaglebone" hostname, and it cause strange (non-informative) behavior of future-based connection.