Replace colors dependency with chalk (svg#1061)

use 'chalk' for colors in console

lib/svgo/coa.js

@@ -1,10 +1,9 @@
 /* jshint quotmark: false */
 'use strict';
 
-require('colors');
-
 var FS = require('fs'),
     PATH = require('path'),
+    chalk = require('chalk'),
     mkdirp = require('mkdirp'),
     promisify = require('util.promisify'),
     readdir = promisify(FS.readdir),
@@ -515,7 +514,7 @@ function printProfitInfo(inBytes, outBytes) {
     console.log(
         (Math.round((inBytes / 1024) * 1000) / 1000) + ' KiB' +
         (profitPercents < 0 ? ' + ' : ' - ') +
-        String(Math.abs((Math.round(profitPercents * 10) / 10)) + '%').green + ' = ' +
+        chalk.green(Math.abs((Math.round(profitPercents * 10) / 10)) + '%') + ' = ' +
         (Math.round((outBytes / 1024) * 1000) / 1000) + ' KiB'
     );
 }
@@ -562,7 +561,7 @@ function showAvailablePlugins() {
     // Flatten an array of plugins grouped per type, sort and write output
     var list = [].concat.apply([], new SVGO().config.plugins)
         .sort((a, b) => a.name.localeCompare(b.name))
-        .map(plugin => ` [ ${plugin.name.green} ] ${plugin.description}`)
+        .map(plugin => ` [ ${chalk.green(plugin.name)} ] ${plugin.description}`)
         .join('\n');
     console.log(list);
 }
@@ -573,7 +572,7 @@ function showAvailablePlugins() {
  * @return {Promise} a promise for running tests
  */
 function printErrorAndExit(error) {
-    console.error(error);
+    console.error(chalk.red(error));
     process.exit(1);
     return Promise.reject(error); // for tests
 }

package.json

@@ -49,8 +49,8 @@
     "jshint": "npm run lint"
   },
   "dependencies": {
+    "chalk": "^2.4.1",
     "coa": "~2.0.1",
-    "colors": "~1.1.2",
     "css-select": "^2.0.0",
     "css-select-base-adapter": "~0.1.0",
     "css-tree": "1.0.0-alpha.28",