Release v0.37.0

[nicoburns]

A release that includes #425 (I'm wanting to use this for value parsing in Taffy, which is currently very low dependency).

Note that cssparser-color v0.4 was never published (see #420). And I think it would still make sense to do so. I believe that all that should be required is to checkout commit 9339ddd which did the version bump for cssparser 0.36 and cssparser-color 0.4, and run cargo publish -p cssparser-color.

It may make sense to align the version numbers of the -color and -macros crates with the main cssparser crate, but I have not done so in this PR.

[nicoburns]

@emilio When you get a chance, could you hit the publish button on this? (+ ideally cssparser-color v0.4 - see PR description above)

[emilio]

Both things are done.

[nicoburns]

Thank you!