Add support for space-separated HSL

[htunnicliff]

This PR adds support for color strings that use space-separated HSL notation described in the CSS Colors Level 4 specification for the hsl() function.

This well-supported update to the hsl() function supports values like these:

hsl(200 50% 25%)
hsl(200 50% 25% / 0.25)

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Changes

• Add tests for space-separated HSL syntax 3b4287c
• Update the regular expression for HSL color strings 9c7c9e8
• Add examples to the README that use space-separated HSL syntax 672b47a

[Qix-]

Man, bizarre. I wonder what the use-case was for them adding this.

Anyway, thanks for the very complete PR :)

[Qix-]

Published as 1.6.0. Thanks again!

[htunnicliff]

Thanks @Qix-! That was one of the fastest open-source PR merges I've ever seen 🚀