add node modules to repo

node_modules/through2/through2.js

@@ -0,0 +1,42 @@
+const Transform = require('stream').Transform || require('readable-stream/transform')
+    , inherits  = require('util').inherits
+    , xtend     = require('xtend')
+
+function noop (chunk, enc, callback) {
+  callback(null, chunk)
+}
+
+function ctor (options, transform, flush) {
+  if (typeof options == 'function') {
+    flush     = transform
+    transform = options
+    options   = {}
+  }
+
+  if (typeof transform != 'function')
+    transform = noop
+
+  function Through2 (override) {
+    if (!(this instanceof Through2))
+      return new Through2(override)
+
+    this.options = xtend(options, override)
+    Transform.call(this, this.options)
+  }
+
+  inherits(Through2, Transform)
+
+  Through2.prototype._transform = transform
+
+  if (typeof flush == 'function')
+    Through2.prototype._flush = flush
+
+  return Through2
+}
+
+function make (options, transform, flush) {
+  return ctor(options, transform, flush)()
+}
+
+module.exports      = make
+module.exports.ctor = ctor