Add P3 and Rec.2020 gamut support

[ai]

Lab and OKLab can be used to generate colors outside sRGB space. We need methods to control it:

1. Method to check that current colors is in sRGB, P3, or Rec.2020 space.
2. If the color is outside, we need a method to convert color to closest color in necessary color space

See also:

• Gamut clipping in CSS spec
• OKLab gamut clipping