Support color changing on slider change

[asaf]

Hey,

How hard would it be to support changing the color on slider value change?
For example starting green towards red color for severity indication,

Thanks.

[whoisandy]

@asaf Could you post an example the above mentioned use case?

[asaf]

@whoisandy I described a use case in the issue, this patch let you change any fill style during rendering, code example to extract a color from a palette based on the current slider's value:

render() {
  const {value} = this.state
  const fillStyle = {'backgroundColor': COLORS[value]}
  return (
            <RangeSlidervalue={value} fillStyle={fillStyle}/>
  )
}

[asaf]

@whoisandy ping?