Design: Organization admin functionality for items outside of organization

Problem to solve

#377477 Address navigating to organization where users can administrate within their organization, but on an instance of GitLab, it is possible for items to exist outside of any organization. This issue is to define and design a method for managing item that fall outside of an organization.

Items to be accounted for (WIP):

• Hardware settings
• Managing users that do not exist as part of an organization

Proposal

Users are handled by the default organization and hardware settings will remain in Admin for the MVC.