[openshift/purge_AWS_resources.py] improve error messages
[openshift/purge_AWS_resources.py] improve error messages

jpopelka/fabric8-analytics-common,jpopelka/fabric8-analytics-common,tisnik/fabric8-analytics-common,tisnik/fabric8-analytics-common,tisnik/fabric8-analytics-common,jpopelka/fabric8-analytics-common