Support #1765 Add Code for Simplereach to D1 only
Adding all_categories function that will return a list of category names for
each category in a category's hierarchy
    e.g.
        ['Defense One', 'Defense One::News']
Pickled categories don't have unicode_name as an attribute. Until that is
fixed, this is the workaround...
Merge branch '1771-sailthru-add-horizon-meta-tags' of github.com:Govexec/django-categories into 1771-sailthru-add-horizon-meta-tags