chore(package): update @istanbuljs/nyc-config-babel to version 2.1.1

Closes #138

Author: greenkeeper[bot]

package.json

@@ -25,7 +25,7 @@
     "babel": "inherit"
   },
   "devDependencies": {
-    "@istanbuljs/nyc-config-babel": "^1.2.2",
+    "@istanbuljs/nyc-config-babel": "^2.1.1",
     "ava": "^0.21.0",
     "babel-core": "^6.25.0",
     "babel-loader": "^7.1.0",