add message to explain this currently only works on jscs master branch

Author: hzoo

README.md

@@ -7,6 +7,7 @@
 **NOTE:** Please note that this is experimental and may have numerous bugs. It has been run against `ember.js` and `babel-core` with no errors (at the moment).
 
 ### Known Issues
+> **Only works on master right now** - `package.json`: `"jscs": "jscs-dev/node-jscs#master",`
 - `validateQuoteMarks`
 
 ### Issues

package.json

@@ -28,7 +28,7 @@
   ],
   "homepage": "https://github.com/jscs-dev/babel-jscs",
   "devDependencies": {
-    "jscs": "^1.13.1",
+    "jscs": "jscs-dev/node-jscs#master",
     "esprima": "^2.2.0",
     "esprima-fb": "^15001.1.0-dev-harmony-fb",
     "mocha": "^2.2.5"