chore(package): update babel-eslint to version 9.0.0

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
   "devDependencies": {
     "ava": "^0.25.0",
     "babel-cli": "^6.26.0",
-    "babel-eslint": "^8.2.6",
+    "babel-eslint": "^9.0.0",
     "babel-plugin-istanbul": "^4.1.6",
     "babel-plugin-transform-export-extensions": "^6.22.0",
     "babel-plugin-transform-object-rest-spread": "^6.26.0",