Fix Private media

Private and unlisted media was no longer showing up in lists.

This happened because we removed the 'manager feed and media' view and replaced it with the regular MediaList view.  This pull request adds a privacy filter to the MediaList to show private and unlisted media that logged-in users have access to.

This PR also adds tests and fixes a few other errors that I found along the way.
It probably isn't necessary, but it might be possible to accidentally create something in the future. When `now()` is used in queries, it prevents potential query caching.