Fixes #8203 - Docker counts displayed on repo info

Docker Images / Docker Tag information can be now
seen in the hammer repository info command

``` bash
$ hammer repository info --id=3
ID:                 3
Name:               fedora/ssh
Label:              fedora_ssh
Organization:       my-org
Red Hat Repository: no
Content Type:       docker
URL:                https://registry.hub.docker.com
Publish Via HTTP:   no
Published At:       https://centos.dev/pulp/repos/my-org/Library/custom/doker/fedora_ssh
Product:            
    ID:   2
    Name: doker
GPG Key:            

Sync:               
    Status:         
    Last Sync Date: 2014/10/24 19:52:11
Created:            2014/10/24 19:51:03
Updated:            2014/10/24 19:51:06
Content Counts:     
    Docker Images: 12
    Docker Tags:   1
```