Enable/Disable share feature

[savva312]

Useage case:
In Course A we would like the students to share the work that they have submitted with others. This is currently available using the activity.
In Course B we want the work submitted by the students to be available only to them and the lecturer. We want to remove the option of allowing them to make their work visible to other students.

Therefore, can we add an additional setting in the Portfolio activity that allows us to enable/disable this functionality. Please see the attached image to clarify which setting we'd like to toggle.