Merge pull request #359 from graphql/greenkeeper/sinon-2.4.1

chore(package): update sinon to version 2.4.1

Author: wincent

package.json

@@ -93,7 +93,7 @@
     "prettier": "^1.3.1",
     "restify": "4.3.0",
     "sane": "2.0.0",
-    "sinon": "2.3.8",
+    "sinon": "2.4.1",
     "supertest": "3.0.0"
   },
   "peerDependencies": {