Merge pull request #37 from eq8/greenkeeper/async-2.1.5

Update async to the latest version 🚀

Author: bbartolome

package.json

@@ -54,7 +54,7 @@
     "npm": ">=2.15.9 <3.0.0"
   },
   "dependencies": {
-    "async": "2.1.4",
+    "async": "2.1.5",
     "bloomrun": "2.3.0",
     "eq8-core": "1.0.4",
     "joi": "9.2.0",