chore(package): update babel-preset-stage-2 to version 6.22.0

https://greenkeeper.io/

Author: greenkeeper[bot]

package.json

@@ -60,7 +60,7 @@
     "babel-eslint": "^7.0.0",
     "babel-polyfill": "^6.16.0",
     "babel-preset-es2015": "^6.16.0",
-    "babel-preset-stage-2": "^6.16.0",
+    "babel-preset-stage-2": "^6.22.0",
     "babel-register": "^6.16.3",
     "commitizen": "^2.8.6",
     "conventional-changelog-cli": "^1.2.0",