add node modules to repo

node_modules/xtend/index.js

@@ -0,0 +1,25 @@
+var Keys = require("object-keys")
+var hasKeys = require("./has-keys")
+
+module.exports = extend
+
+function extend() {
+    var target = {}
+
+    for (var i = 0; i < arguments.length; i++) {
+        var source = arguments[i]
+
+        if (!hasKeys(source)) {
+            continue
+        }
+
+        var keys = Keys(source)
+
+        for (var j = 0; j < keys.length; j++) {
+            var name = keys[j]
+            target[name] = source[name]
+        }
+    }
+
+    return target
+}