Move EE-only controllers, helpers, models, and services to top-level ee directory
What does this MR do?
Move EE-only controllers, helpers, models, and services to top-level ee directory
Are there points in the code the reviewer needs to double check?
no
What are the relevant issue numbers?
Part of https://gitlab.com/gitlab-org/gitlab-ee/issues/3107 and https://gitlab.com/gitlab-org/gitlab-ee/issues/3970