Sort and de-dupe image listings
Sort and de-dupe image listings

Fixes TOOLS-340

gholms/euca2ools,gholms/euca2ools,vasiliykochergin/euca2ools,nagyistoce/euca2ools,jhajek/euca2ools,nagyistoce/euca2ools,vasiliykochergin/euca2ools,jhajek/euca2ools