Provide support for `NO_COLOR` environment variable

[mjf]

Please, see here. It's ~~quite~~ common to provide support for this environment variable nowadays.

[mjf]

I would also suggest to provide something like NO_EMOJI to supress the fancy wide characters in the output. The two options together let users to choose either combination of both (fancy but no colors, fancy and colors and non-fancy without colors). :)

[MrDowntempo]

Having NO_EMOJI attempt to fallback to nerdfont characters might be a nice option too.