Move all non-filter settings into a real settings screen.

[smichel17]

This does a bunch of good things:

• Makes the main screen non-scrollable. Scrollable screens with seekbars in them are a pain.
• Reduces the amount of nested subscreens by flattening all other settings into a single screen. We can do this now because we don't need to worry about scrolling on the main screen.
• Adds the possibility of rewriting the filter settings UI into something that can sit on top of other apps, so you can get a real-time preview as you adjust them (like Night Screen).