fix(package): update babel-core to version 6.23.1 (#1122)

https://greenkeeper.io/

package.json

@@ -44,7 +44,7 @@
   "dependencies": {
     "accepts": "1.3.3",
     "ansi-html": "0.0.7",
-    "babel-core": "6.22.1",
+    "babel-core": "6.23.1",
     "babel-generator": "6.22.0",
     "babel-loader": "6.2.10",
     "babel-plugin-module-resolver": "2.5.0",