Improve docs on color space conversion

[0x7CFE]

Current crate documentation does not provide a section that covers color space conversion. I may suggest adding "color conversion" chapter somewhere near top-level documentation index.

Such a section should probably include brief description of different color spaces and typical scenarios, like conversion from HSV to sRGB and vice versa.

[Ogeon]

Thanks, this is good feedback. It should be possible to have some kind of summary of the main features. 👍