chore(package): update dateformat to version 3.0.1

Author: greenkeeper[bot]

package.json

@@ -25,7 +25,7 @@
     "@types/form-data": "2.2.0",
     "@types/mocha": "2.2.43",
     "codecov": "2.3.0",
-    "dateformat": "3.0.0",
+    "dateformat": "3.0.1",
     "execa": "0.8.0",
     "fetch-mock": "5.12.2",
     "http-server": "0.10.0",