Merge pull request #3 from aureooms/greenkeeper/ava-0.19.1

Update ava to the latest version 🚀

Author: Aurélien Ooms

package.json

@@ -28,7 +28,7 @@
     "@aureooms/js-itertools": "^3.1.1"
   },
   "devDependencies": {
-    "ava": "^0.18.0",
+    "ava": "^0.19.1",
     "babel-cli": "^6.18.0",
     "babel-polyfill": "^6.16.0",
     "babel-preset-latest": "^6.16.0",