Fixes #7953: add product/repositories list for an erratum.

Display a list of products/repositories that an erratum is in.

http://projects.theforeman.org/issues/7953
I don't think this will work if an array is not specified.  You have to do something like:

``` params[:content_view_version_id] = [ params[:content_view_version_id] ] unless  params[:content_view_version_id].is_a?(Array)```