Ability to purge orphan Files from the asset Manager

Who would benefit?

Any company who deletes Resource entities

What impact would it make?

Release storage space

How should it work?

Upon a click a background process should iterate all of the stored blobs in the file store and delete any which are NOT being used by any of the current Resources.

Current implementation is that deleting a Resource leaves an orphan blob. Similarly, replacing the media of a Resource leaves an orphan blob too.

Why is it needed?

We get billed by consumed storage space