install gulp to process code

node_modules/path-root-regex/index.js

@@ -0,0 +1,13 @@
+/*!
+ * path-root-regex <https://github.com/jonschlinkert/path-root-regex>
+ *
+ * Copyright (c) 2016, Jon Schlinkert.
+ * Licensed under the MIT License.
+ */
+
+'use strict';
+
+module.exports = function() {
+  // Regex is modified from the split device regex in the node.js path module.
+  return /^([a-zA-Z]:|[\\\/]{2}[^\\\/]+[\\\/]+[^\\\/]+)?([\\\/])?/;
+};