Duplicate images protected by a course when cloning that course

**Is your feature request related to a problem? Please describe.**
When cloning a course that has media protected by the original course, any media included in lessons within the cloned course will still be protected by the old (original) one.

**Describe the solution you'd like**
Duplicate media that is protected by the old course into the new one, or prompt if the user wants to duplicate that content. Update references to the original media to the new one in the cloned lesson content and elsewhere in the course (ie. quizzes).

**Describe alternatives you've considered**
Leave the content as-is and inform the user that they would need to update the protection or upload content again.