IssueTracker

Currently it is difficult to assign widths or heights to elements inside of a layout that are relative to their parent or allocated space.

For instance if I want a column of 3 items with width of 50% the parent width, how do I accomplish that right now?

I believe flutter has a way to do this with percentages, as does Yoga and CSS on the web. Should we consider adding something similar?

```
inline class Percent(@FloatRange(from=0f, to=100f) val value: Float)
fun Modifier.width(widthInPercent: Percent) = ...
```

Additional context: https://twitter.com/bernaferrari/status/1284233008405458945