Restrict Access when course is complete

[bozoh]

Is your feature request related to a problem? Please describe. by @gonzalorti take the opportunity to suggest a possible improvement. In these options I can chose to restrict access until an selected activity is marked as completed. But I can't find a way to restrict access until all the activities with completion are completed. For me, it should be very useful, as this is a very logical requirement. To get this, each time I create a new activity in the course, I have to add it in the certificate restrictions.

Regards,

see #208