install gulp to process code

node_modules/path-root/index.js

@@ -0,0 +1,21 @@
+/*!
+ * path-root <https://github.com/jonschlinkert/path-root>
+ *
+ * Copyright (c) 2016, Jon Schlinkert.
+ * Licensed under the MIT License.
+ */
+
+'use strict';
+
+var pathRootRegex = require('path-root-regex');
+
+module.exports = function(filepath) {
+  if (typeof filepath !== 'string') {
+    throw new TypeError('expected a string');
+  }
+
+  var match = pathRootRegex().exec(filepath);
+  if (match) {
+    return match[0];
+  }
+};