Open Stack

The server backup API was added 8 years ago. It has Nova basically 
implementing a poor-man's cron for some unknown reason (probably because 
the original RAX Cloud Servers API had some similar or identical 
functionality, who knows...).

Can we deprecate this functionality please? It's confusing for end users 
to have an `openstack server image create` and `openstack server backup 
create` command where the latter does virtually the same thing as the 
former only sets up some whacky cron-like thing and deletes images after 
some number of rotations.

If a cloud provider wants to offer some backup thing as a service, they 
could implement this functionality separately IMHO, store the user's 
requested cronjob state in their own system (or in glance which is kind 
of how the existing Nova createBackup functionality works), and run a 
simple cronjob executor that ran `openstack server image create` and 
`openstack image delete` as needed.

This is a perfect example of an API that should never have been added to 
the Compute API, in my opinion, and removing it would be a step in the 
right direction if we're going to get serious about cleaning the Compute 
API up.

Thoughts?
-jay