[hotfix] Added missing dependency. (#18)

Author: neogeek

package.json

@@ -14,6 +14,7 @@
     "chalk": "2.4.2",
     "jsdom": "15.2.1",
     "meow": "5.0.0",
+    "mkdirp": "0.5.1",
     "request": "2.88.0",
     "update-notifier": "3.0.1"
   },