Files in iCloud Drive don't show up unless downloaded locally

[jbmorley]

Currently, files in iCloud Drive don't show up unless they've already been explicitly downloaded by the user. We should ensure we show all files irrespective of their iCloud status and allow users to download remote files directly within the app.

[jbmorley]

Definitely an important issue for first ship as most users will likely use iCloud Drive.

[jbmorley]

I'm not actually sure how this works with iCloud Drive on macOS when files haven't been downloaded (I have all files downloaded locally automatically).