RFC: Redesign the media previews

[samdroid-apps]

Right now there are media previews in the sublist (click the tumbnail to open a popover). They are very buggy (eg. #6), but are a simple MVP.

I haven't found them very useful. In fact I haven't used them in the last few months. I would like to remove or redesign them. I don't have many thoughts, and would appreciate any comments on what you would like, how you use the current system, etc.