Add method for set thumbs radius

[comm1x]

Default size of thumbs is too big (comparing with native elements). But I do not found method for changing radius and forced to override CrystalRangeSeekbar:

public class PatchedCrystalRangeSeekbar extends CrystalRangeSeekbar {
    private final int mThumbsSize = 30;

    // ... override constructors

    @Override
    protected float getThumbWidth() {
        return mThumbsSize;
    }

    @Override
    protected float getThumbHeight() {
        return mThumbsSize;
    }
}

It will be great to create method or style for changing default radius.

[syedowaisali]

available in future release