[Feature Request] Add a "public / not public" flag to media

[DBinaghi]

In some particular cases, repository's admins might need to hide certain medias while allowing users/visitors to see the relative infos / Item. It might be, for example, a situation where copyright for some of the medias saved in the repository does not allow for their display.

An extra "public" flag in the file table, together with code that hides to non-admin/owner whatever is not public, could do the trick, maybe.

Default would be "public", so no damage would be done to whomever does not want to use the feature. Possibly, an "ignore media public flag" in the general settings could be added, for admins to ensure that no media will be hidden, no matter what.

[ankana1996]

I support this feature as I'm facing some issues regarding control over access to media.