[Material] Circular Progress Indicator

[PureWeen]

Material Circular Progress Indicator

https://material.io/design/components/progress-indicators.html#circular-progress-indicators

• Visually Identical
  The rendering should be such that the naked eye can’t tell the difference at a glance. Not to be confused with “pixel perfect”

ActivityIndicator doesn't expose very many apis so the expectation here is that the default would size and color itself the same on iOS and Android

The hopefully not too tricky part here will be that there is only a Material Activity Indicator on iOS. On the android one it's still just using the original control so material visual on Android will just apply default styles or just inherit from the existing renderer

Current state of implementation

Scenarios

<ActivityIndicator Visual="Material"  />

Difficulty : medium