feat: add --no-color

Some terminals do not support colors and will output a bunch of
unnecessary clutter instead. This creates `-n|--no-color` which disables
color completely

packages/sirv-cli/bin.js

@@ -19,6 +19,7 @@ sade('sirv [dir]')
 	.option('-G, --gzip', 'Send precompiled "*.gz" files when "gzip" is supported', true)
 	.option('-B, --brotli', 'Send precompiled "*.br" files when "brotli" is supported', true)
 	.option('-m, --maxage', 'Enable "Cache-Control" header & define its "max-age" value (sec)')
+	.option('-n, --no-color', 'Disables colored output')
 	.option('-i, --immutable', 'Enable the "immutable" directive for "Cache-Control" header')
 	.option('-k, --http2', 'Enable the HTTP/2 protocol. Requires Node.js 8.4.0+')
 	.option('-C, --cert', 'Path to certificate file for HTTP/2 server')

packages/sirv-cli/index.js

@@ -34,6 +34,10 @@ module.exports = function (dir, opts) {
 	dir = resolve(dir || '.');
 	opts.maxAge = opts.m;
 
+	if (opts.no_color) {
+		colors.enabled = false
+	}
+
 	if (opts.cors) {
 		opts.setHeaders = res => {
 			res.setHeader('Access-Control-Allow-Origin', '*');