Merge pull request #68 from telemark/greenkeeper/ava-0.22.0

Update ava to the latest version 🚀

Author: zrrrzzt

package.json

@@ -41,7 +41,7 @@
   },
   "homepage": "https://github.com/telemark/node-dsf",
   "devDependencies": {
-    "ava": "0.21.0",
+    "ava": "0.22.0",
     "coveralls": "2.13.1",
     "nsp": "2.7.0",
     "nyc": "11.1.0",