Manually choose which courses and/or lessons are required for completion

Allow admins to decide on a lesson & course level that the content is optional. We have a few courses in a curriculum that we don't want to be required in order to receive the certificate. We also have use cases when a lesson within a course isn't necessary in order to complete the course. Our saas product is very customizabe, so we want users to be able to skip content that does not apply to them, but want to include it in the main curriculum for those that need to know.

The current option to designate a number of courses that count for completion is not specific enough.