fixes #5631 - API v2 - host and hostgroups show.json.rabl should show all puppetclasses in child node

fixes #4204 - add config groups feature - assign multiple config groups to a host or hostgroup

fixes #4349 - API v2 - add location and organization child nodes to user, domain, subnet, etc show json templates

fixes #4198 - API v2 - add child nodes to show responses. Ex. architecture should show operating systems node

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

fixes #2931 - API v2 hosts JSON response, add *_name for each *_id

fixes #3017 - split APIv2 controllers from v1 parents