Restrict to node v0.10 since v0.11 introduces v8 incompatibility

package.json

@@ -23,6 +23,6 @@
     "test": "vows --spec"
   },
   "engines": {
-    "node": ">= 0.10.0"
+    "node": ">=0.10.0 <0.11"
   }
 }