Glance/ImageAliases

Summary
Users don't always care about the exact version of their chosen OS or snapshot. Only that the OS is the most recent or the application snapshot is the most stable. Image aliases would fix this. Rather than knowing to pick "RHEL 6.4-24017" vs "RHEL 6.4-25001" the users could choose "RHEL 6.X" which the image admin would keep pointed to the most up to date and stable version of that OS or application image. Similarly for applications the provider could maintain Test, Stable, Quarantine, etc aliases which point to the most recent of each type. Ideally these aliases should be at the top of the list, with the actual disk images listed after. And further, the ability to hide the names of the actual disk images would make it even less confusing for the consumers of the disk images.

Assumptions

 * 1) You don't need to delete and recreate your disk alias object to change which disk image it points to.
 * 2) If you rebuild your VM, it will be recreated with whatever the alias is pointing to /right now/, and not reuse its original base image.