Allow a group to have multiple owners
Created by: fernandolopez
Only the owner of a group can transfer or create projects on a group.
It would be useful to have groups in which multiple users can create new projects.
This issue is similar to #3269 (closed) but with the solution suggested on: http://feedback.gitlab.com/forums/176466-general/suggestions/3797812-allow-group-members-to-add-projects