[Base] Terminology for docker/atomic images

[Dusty Mabe]

Hi All,

Per discussion in the #fedora-cloud meeting last Friday I would like to
start a thread about the names of the Docker and Atomic deliverables for F21. 

I know of at least a few cases where there has been confusion regarding
what deliverable has been the subject of a conversation on IRC as a result
of the current terminology. I've seen the docker and atomic referred to as:

    Docker Image
    Atomic Image
    Docker Host Image
    etc...

It seems like the one that sparks the most confusion is "Docker Image".
Usually when I see "Image" I think a VM bootable image (i.e. virtualization, 
not containers/Docker). A progression from that misunderstanding could lead
one to think that "Docker Image" is the VM disk image I can use to boot a
host that will run the Docker daemon and thus run containers.

I think it would be nice to help ourselves and our users along by separating 
the terminology a bit such that it is hard to confuse what is a VM disk
image vs. what is an image for use with Docker.

Here is a first stab at trying to make things clearer:


    Docker Container Image - base container image - can be used with docker 
    Atomic Image           - minimal OS, Atomic updates, aka 'Docker Host'


In a nutshell, it would be great if we added "Container" to references we
make to the container image (in conversation and docs).

Thoughts?

Dusty