Results 2 issues of Kevin Scully

Right now there is no way to adjust the `intensity`. Let me know if I'm missing something or if I can just add a pull request with the change.

I'm trying to dynamically change it from a spinner to an initalValue. When I change the spinnerMode property from an outside widget I see this: `_SleekCircularSliderState is a SingleTickerProviderStateMixin but...