Merge pull request mozilla#341 from mozilla/greenkeeper-eslint-3.0.0

Update eslint to version 3.0.0 🚀

Author: kumar303

package.json

@@ -72,7 +72,7 @@
     "chai": "3.5.0",
     "coveralls": "2.11.9",
     "deepcopy": "0.6.3",
-    "eslint": "2.13.1",
+    "eslint": "3.0.0",
     "flow-bin": "0.27.0",
     "grunt": "1.0.1",
     "grunt-contrib-clean": "1.0.0",