chore(package): update eslint-config-airbnb-base to version 13.0.0

Closes #87

Author: greenkeeper[bot]

package.json

@@ -30,7 +30,7 @@
   "devDependencies": {
     "coveralls": "^2.11.9",
     "eslint": "^4.4.1",
-    "eslint-config-airbnb-base": "^11.0.1",
+    "eslint-config-airbnb-base": "^13.0.0",
     "eslint-plugin-import": "^2.7.0",
     "ghooks": "^2.0.0",
     "istanbul": "^0.4.4",