Support for FORCE_COLOR

[cardil]

It would be a good idea to apart from supporting NO_COLOR to support easy forcing of color output.

The FORCE_COLOR environmental variable is less spread across industry, but still is used in a couple of libraries, i.e. https://github.com/chalk/chalk#supportscolor

[juanzolotoochin]

For anyone else who finds this issue, I'm using this workaround:

import "github.com/fatih/color"

func ForceColor() {
	color.NoColor = false
}

Then I just call this at the top of main()

[pellared]

FORCE_COLOR becomes a standard: https://force-color.org/

[pellared]

I think it may be worth to resurrect #156

[cloudyparts]

FORCE_COLOR option is needed for CI jobs. Gitlab CI supports colorized output in job logs. CI Jobs TERM is set to "dumb" which mutes colors in this package.

[cardil]

@fatih Would you reconsider your opinion, as https://force-color.org becoming a standard?