fix(package): update async to version 3.2.0

Closes #24

Author: greenkeeper[bot]

package.json

@@ -26,7 +26,7 @@
   "author": "Diego Rodríguez Baquero <[email protected]> (https://diegorbaquero.com)",
   "license": "MIT",
   "dependencies": {
-    "async": "3.1.0",
+    "async": "3.2.0",
     "babylon": "^6.18.0",
     "babylon-walk": "^1.0.2",
     "chalk": "3.0.0",