Turn BaseStyles members into a table containing type, default value, and inheritance state, generate BaseStyles.Defaults
Auto-generate layout cascading based on inheritance state
Use BaseStyles.Default instead of hardcoding defaults
Similar to `css-defaults` branch but this does it better - so I'm
deleting that in favour of this.
Rather than hard-coding the default value every time we fetch it:
```cs
var value = Styles.BackgroundColor ?? Color.White;
```
We should be doing something like:
```cs
var value = Styles.BackgroundColor ?? Default.BackgroundColor;
```
Provide default values as fallbacks for style transitions, use LerpProperty inside BaseStyles.FromLerp
In FromLerp, check if the property we're trying to change is actually changing
Prevents us from stomping property changes when a transition is running
with `transition: all` if you have an animation running simulataneously
Move default styles into `DefaultStyles`, make everything readonly