Accept additional hex color aliases (w, 1, 0, -1)

[ShrimpCryptid]

Use Case

Extension off of #306.

From @toloudis:

also suggest allowing 0 for black, and 1 or (maybe more appropriately) -1 for white, as well. Something about that feels more consistent than having a non-numeric letter character. See what you think. If not today, then we can consider it for a future PR.

See TODOs in url_utils.ts.

Solution

Please describe your ideal solution

Alternatives

Please describe any alternatives you've considered, even if you've dismissed them