chore(package): update babel-core to version 6.17.0

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -26,7 +26,7 @@
   },
   "devDependencies": {
     "babel-cli": "^6.10.1",
-    "babel-core": "^6.9.1",
+    "babel-core": "^6.17.0",
     "babel-eslint": "^7.0.0",
     "babel-loader": "^6.2.4",
     "babel-preset-es2015": "^6.9.0",