content views : fix nav to use Katello.config vs AppConfig
content views - update nav to ensure unique ids

After the nav was written, there were changes made in
master to ensure that each nav element had a unique
id.  This commit is to ensure the same for content
views.
content views - rename nav Views to Content View Definitions

Oops... forgot to make this change earlier...

When definitions were initially added to the nav, the text
was too long and Changesets would drop off.  Since that time,
the page layout has been increased as well as there have
been changes to the navs to address the spacing issue.  As
a result, updating the label to align with the original
mockup.
Merge pull request #1557 from bbuckingham/fork_content_views_fencing

content views - ui - minor changes on the nav