chore(package): update ava to version 3.6.0

Closes #202

Author: greenkeeper[bot]

package.json

@@ -110,7 +110,7 @@
     "@types/tmp": "^0.0.32",
     "app-root-path": "^2.0.1",
     "awesome-typescript-loader": "^3.0.8",
-    "ava": "^0.18.2",
+    "ava": "^3.6.0",
     "babel-loader": "^6.3.2",
     "babel-plugin-espower": "^2.3.2",
     "babel-plugin-dynamic-import-node": "^1.2.0",