User roles

I ended up using rolify and pundit to describe roles and authorization. This implements policies and roles, but at the moment only partially implements checking them in controllers. 
I assume these visibility levels to determine which user role can access what? E.g. my project has dev visibility so only the project collaborator's can access it.

Were you thinking about using [Pundit scopes](https://github.com/elabs/pundit#scopes) for index / enumeration actions?