Add COLOR argument type for Slash Commands

[thunderstorm010]

Description
Add a COLOR type for slash commands. Two options to enter colors, hex and names. If a color name is entered, it should be translated by the client/Discord to English before sending to the bot.

Why This is Needed
Bots can use colors to generate images and do other things.

Alternatives Considered
Using a string type for colors and manually separate them between hex and color names.

Additional Details
The color string should also be able to take specific color names or colors in a specific range. (defined by the bot).

[k9lego]

I support this, it would especially be useful for changing role color

[Sxigames]

totally support

[CottageDwellingCat]

It might be better to translate always the color to a hex value, or having color-name and color-hex be separate options so that bots don't have to filter the input.

[sairam4123]

Just have it as a color picker, so users don't have to find the color from browser.

[Nv7-GitHub]

I think a color picker option would be super useful, Discord already has one in the role menu, the API could respond in the same color type as role colors work

[Milo123459]

Perhaps colour picker options can have the background of the option be the colour that you pick?

[JDJGInc]

I think that would fit really well, and they could probaly reuse an already existing color picker on other parts of the site.

may work a bit of modification though

[x5dfg]

This good function for hex or rgb input

[JDJGInc]

Discord could use the builtin color picker.
and possibly translate decimal, hex (already supported), or rgb.