fixes #3646 - API v2 change default root name for api json single object response to no root node but make it configurable

fixes #3137 - API v2 - show error if optional nested object does not exist for nested route

fixes #3018 - API v2 metadata for pagination, search, order in index collection json response

fixes #3011 - default root node name for api collections json response to :results but make it configurable

fixes #3736 - users API uses login name as an identifying attribute

fixes #3510 - plugin interface for registering a plugin, updated menu system

fixes #2763 - correcting doco links

fixes #3017 - split APIv2 controllers from v1 parents

fixes #3597 - removing rr gem, make tests consistent by using just mocha

fixes #3566 - exposes orchestration tasks via the API at /api/orchestration/id/tasks