Support colorful prompt

[jievince]

liner doesn't support colorful prompt now:

func (s *State) PromptWithSuggestion(prompt string, text string, pos int) (string, error) {
	for _, r := range prompt {
		if unicode.Is(unicode.C, r) {
			return "", ErrInvalidPrompt
		}
	}

Why liner doesn't prompt like \033[31;1m\033[0m ?

[jievince]

@peterh

[peterh]

Liner doesn't support \033 because it's not portable. Specifically, Windows doesn't support VT102 escape sequences. It has a completely different API.

If you want colour, you want something more powerful (and less opinionated) than liner.