Constant siege_color::rec2020::REC2020_CHROMATICITIES

pub const REC2020_CHROMATICITIES: Chromaticity = Chromaticity{red: Vec2{x: 0.708, y: 0.292,},
             green: Vec2{x: 0.170, y: 0.797,},
             blue: Vec2{x: 0.131, y: 0.046,},
             white: Vec2{x: 0.3217, y: 0.3290,},}