base_painter.dart needs more customization

[SaadArdati]

The section lines can be more customizable and I wish for that right now

https://github.com/davidanaya/flutter-circular-slider/blob/master/lib/src/base_painter.dart#L37-L43

    if (primarySectors > 0) {
      _paintSectors(primarySectors, 8.0, selectionColor, canvas);
    }

    if (secondarySectors > 0) {
      _paintSectors(secondarySectors, 6.0, baseColor, canvas);
    }

the radiusPadding can be made customizable and the secondarySector should not use the baseColor, but rather allow a custom one and default to baseColor