Refactor styling

[frederoni]

Made a few changes here since trait collections are usually applied per property, not per style.
This also makes it a lot more convenient to style components that aren't explicitly exposed in the style.

A custom night style would look something like this:

class CustomNightStyle: DayStyle {
    
    required init() {
        super.init()
        mapStyleURL = URL(string: "mapbox://styles/mapbox/satellite-streets-v9")!
        styleType = .nightStyle
    }
    
    override func apply() {
        super.apply()
        ManeuverView.appearance().backgroundColor = #colorLiteral(red: 0.2974345386, green: 0.4338284135, blue: 0.9865127206, alpha: 1)
        RouteTableViewHeaderView.appearance().backgroundColor = #colorLiteral(red: 0.2974345386, green: 0.4338284135, blue: 0.9865127206, alpha: 1)
    }
}

@bsudekum 👀

[bsudekum]

While we're at it, want to add a StyleType enum to this style and also add a custom dark theme? Would be cool to show custom night/day switching styles in the example.

[frederoni]

Fixed in 29b1269

[bsudekum]

This is sort of a confusing case. It's sort of half the default case since we're not passing in the default dark style? Thoughts on reverting this change?

[frederoni]

Ah, yeah, this was just to force the light style while working on it.

[bsudekum]

This is looking good, however I'm getting the default dark style (during the day) in the demo app.

[frederoni]

@bsudekum We should be good to ✅ here.

[bsudekum]

This needs documentation.

[bsudekum]

documentation needed.

[bsudekum]

Looks good, added few doc comments.