v2.1.1 fix https://github.com/nodejs/security-wg/pull/211

package.json

@@ -12,7 +12,7 @@
   ],
   "author": "AJ ONeal <coolaj86@gmail.com> (https://coolaj86.com)",
   "engines": {
-    "node": ">= 0.4.0"
+    "node": ">= 4.5.0"
   },
   "main": "node-atob.js",
   "browser": "browser-atob.js",
@@ -20,5 +20,5 @@
     "atob": "bin/atob.js"
   },
   "license": "(MIT OR Apache-2.0)",
-  "version": "2.1.0"
+  "version": "2.1.1"
 }