Split Saturate into Saturate and Desaturate

[Ogeon]

The Saturate trait is split to give us a separate Desaturate trait, and *Assign variants are added. Just like how Shade was changed. I did also notice a small bug in how DarkenAssign was blanket implemented.

Breaking Change

desaturate and desaturate_fixed have been moved into a Desaturate trait. Saturate does also not require/imply Sized, and Saturate::Scalar does no longer require/imply Float.

[github-actions]

Benchmark for e229bba

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Cie family/lab to lch	3.5±0.04µs	3.6±0.01µs	-2.78%
Cie family/lab to xyz	982.5±13.08ns	1034.2±71.06ns	-5.00%
Cie family/lch to lab	2.5±0.04µs	2.7±0.11µs	-7.41%
Cie family/linsrgb to xyz	4.0±0.04µs	4.1±0.00µs	-2.44%
Cie family/xyz to lab	10.8±0.17µs	11.5±0.53µs	-6.09%
Cie family/xyz to yxy	634.2±4.85ns	668.7±71.13ns	-5.16%
Cie family/yxy to xyz	685.7±2.10ns	721.8±72.18ns	-5.00%
Matrix functions/matrix_inverse	13.9±0.13ns	14.1±0.02ns	-1.42%
Matrix functions/multiply_3x3	10.9±0.09ns	11.0±0.01ns	-0.91%
Matrix functions/multiply_rgb_to_xyz	4.9±0.06ns	4.9±0.01ns	0.00%
Matrix functions/multiply_xyz	4.8±0.07ns	4.9±0.02ns	-2.04%
Matrix functions/multiply_xyz_to_rgb	4.9±0.06ns	5.1±0.19ns	-3.92%
Matrix functions/rgb_to_xyz_matrix	25.4±0.21ns	25.6±0.04ns	-0.78%
Rgb family/hsl to hsv	853.6±6.14ns	851.7±5.44ns	+0.22%
Rgb family/hsl to linear hsl	9.6±0.02µs	9.6±0.06µs	0.00%
Rgb family/hsl to rgb	2.6±0.12µs	2.6±0.01µs	0.00%
Rgb family/hsv to hsl	1296.7±9.92ns	1270.2±8.20ns	+2.09%
Rgb family/hsv to hwb	275.4±2.95ns	277.4±0.77ns	-0.72%
Rgb family/hsv to linear hsv	9.3±0.49µs	8.9±0.03µs	+4.49%
Rgb family/hsv to rgb	2.5±0.02µs	2.5±0.02µs	0.00%
Rgb family/hwb to hsv	630.7±6.16ns	632.3±3.39ns	-0.25%
Rgb family/hwb to linear hwb	9.7±0.01µs	9.7±0.06µs	0.00%
Rgb family/linear hsl to hsl	10.4±0.03µs	10.3±0.11µs	+0.97%
Rgb family/linear hsv to hsv	9.8±0.08µs	9.8±0.04µs	0.00%
Rgb family/linear hwb to hwb	10.8±0.37µs	11.0±1.30µs	-1.82%
Rgb family/linsrgb to rgb	4.8±0.00µs	4.8±0.05µs	0.00%
Rgb family/linsrgb_f32 to rgb_u8	6.5±0.03µs	6.5±0.06µs	0.00%
Rgb family/rgb to hsl	878.9±6.84ns	894.6±25.51ns	-1.75%
Rgb family/rgb to hsv	670.3±5.86ns	672.8±1.89ns	-0.37%
Rgb family/rgb to linsrgb	5.1±0.05µs	5.4±0.21µs	-5.56%
Rgb family/rgb_u8 to linsrgb_f32	5.5±0.06µs	5.5±0.02µs	0.00%
Rgb family/xyz to linsrgb	7.7±0.07µs	7.8±0.01µs	-1.28%

[Ogeon]

Oh I almost forgot...

bors r+

[bors]

Build succeeded:

• ci