Merge pull request #60 from akikoo/greenkeeper/sinon-4.0.0

Update sinon to the latest version 🚀

Author: akikoo

package.json

@@ -22,7 +22,7 @@
     "babel-preset-react": "^6.16.0",
     "jsdom": "^11.0.0",
     "mocha": "^3.4.0",
-    "sinon": "^3.0.0",
+    "sinon": "^4.0.0",
     "unexpected": "^10.18.0",
     "unexpected-sinon": "^10.1.1"
   }