Description
In the new (0.8) web UI, the "Application Detail UI" link on the Application Info page is derived from Utils.getLocalHostName(). When running on EC2, this link will break if the local hostname isn't the public EC2 hostname.
In SPARK-613, we fixed a similar problem by introducing a masterPublicAddress variable that's populated from SPARK_PUBLIC_DNS if it's set. We should probably do something similar here.