chore(package): update eslint-config-airbnb to version 9.0.0 (#35)

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -50,7 +50,7 @@
     "dirty-chai": "^1.2.2",
     "enzyme": "^2.2.0",
     "eslint": "^2.4.0",
-    "eslint-config-airbnb": "^8.0.0",
+    "eslint-config-airbnb": "^9.0.0",
     "eslint-plugin-import": "^1.6.0",
     "eslint-plugin-jsx-a11y": "^1.0.3",
     "eslint-plugin-react": "^5.0.0",