replaced deprecated gulp-util (#34)

* replaced deprecated gulp-util

* removed package-lock.json

index.js

@@ -1,10 +1,11 @@
 'use strict';
 var through = require('through2'),
   uglify = require('uglify-es'),
-  gutil = require('gulp-util'),
   minimatch = require('minimatch'),
   path = require('path'),
-  PluginError = gutil.PluginError,
+  File = require('vinyl'),
+  PluginError = require('plugin-error'),
+  colors = require('ansi-colors'),
   reSourceMapComment = /\n\/\/# sourceMappingURL=.+?$/,
   pathSeparatorRe = /[\/\\]/g;
 
@@ -39,9 +40,9 @@ function formatError(error, file) {
   filePath = filePath ? filePath : file.path;
   relativePath = path.relative(process.cwd(), filePath);
 
-  message += gutil.colors.underline(relativePath) + '\n';
+  message += colors.underline(relativePath) + '\n';
   message += error.message + ' (line: ' + error.line  + ', col: ' + error.col + ', pos: ' + error.pos;
-  error.message = gutil.colors.red(message);
+  error.message = colors.red(message);
   return error;
 }
 
@@ -104,7 +105,7 @@ module.exports = function(opt) {
     }
     options.fromString = options.hasOwnProperty("fromString") ? options.fromString : true;
 
-    var min_file = new gutil.File({
+    var min_file = new File({
       path: Array.isArray(ext.min) ? file.path.replace(ext.min[0], ext.min[1]) : file.path.replace(/\.js$/, ext.min),
       base: file.base
     });

package.json

@@ -12,10 +12,12 @@
   },
   "author": "taojie.hjp@taobao.com",
   "dependencies": {
-    "gulp-util": "^2.2.14",
+    "ansi-colors": "^1.0.1",
     "minimatch": "^3.0.2",
+    "plugin-error": "^0.1.2",
     "through2": "^0.4.0",
-    "uglify-es": "^3.0.3"
+    "uglify-es": "^3.0.3",
+    "vinyl": "^2.1.0"
   },
   "license": "ISC",
   "bugs": {