[Permissions] More granular course visibility

Problem statement:

At present, Canvas permissions allow us to enable or disable "Courses - change visibility" which allows an instructor to choose between Course, Institution, and Public visibility. At our institution, we don't want instructors to be able to make courses publicly visible, but in order to remove this ability, we must also remove their ability to set "institutional" visibility--which we don't want to do.

Proposed solution:

Make this permission more granular so that we can control which options instructors can select from this menu. Create separate permissions for setting institutional and public visibility.

User role(s):

admin,instructor