downgrade grunt-eslint back to 18.0.0 for node 0.10 compatibility

Author: nirnatan

package.json

@@ -45,7 +45,7 @@
   },
   "devDependencies": {
     "grunt": "^1.0.1",
-    "grunt-eslint": "^19.0.0"
+    "grunt-eslint": "^18.0.0"
   },
   "peerDependencies": {
     "grunt": "^1.0.0"