chore(package): update ava to version 0.16.0

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -25,7 +25,7 @@
     "validator": "^5.7.0"
   },
   "devDependencies": {
-    "ava": "^0.14.0",
+    "ava": "^0.16.0",
     "coveralls": "^2.11.9",
     "eslint": "^3.5.0",
     "eslint-config-punchcard": "^1.0.1",