fixes #3339 - nested fact support, allow fact importers to be registered by plugins

fixes #3693 - API v2 - accept GET json format of object in PUT/POST requests to add/remove has_many associations

Fixes #3721 - Map OS family to a display variant

Fixes #3720 - Add description field to operatingsystem

refs #3067 - domain stripped from installation media hostname for Solaris

Fixes #3753 - always use main_app to determine paths for running an isolated namespace plugin

fixes #3790 - Added support for isolated engine to foreman menu

Fixes #3838: Adds ability to define a divider when declaring a menu item
from a plugin.

fixes #3491 - API v2 rabl templates base, main, show for each controller

i18n - extracting new, updating rails, pulling from tx