Add missing simplex-noise module

examples/node/package.json

@@ -6,7 +6,8 @@
   "dependencies": {
     "flags": "~0.1.1",
     "midi": "~0.8.1",
-    "minimist": "~0.0.8"
+    "minimist": "~0.0.8",
+    "simplex-noise": "~2.1.1"
   },
   "private": true
 }