update user_can_view_profile to check for "viewalldetails"

This is covered by unit tests, but we'll check anyway Make sure there are no courses on your site. We don't want interference here. As admin user, create a course and enrol a student. Remember the student id Now, assign a course creator at system level. Log in as the course creator and view your profile Swap the ?id=x for the student id and confirm that you can't access the profile. Now, log in as admin again and edit the course creator role. Grant the 'viewalldetails' capability to this role. Now, log in as the course creator again and try to view the student profile like you did before. Confirm that you are able to view the student profile Clean up: Remove the 'viewalldetails' capability from the course creator role.