chore(package): update mkdirp to version 1.0.4

Closes #213

Author: greenkeeper[bot]

package.json

@@ -132,7 +132,7 @@
     "cpy-cli": "^1.0.1",
     "esdoc": "^0.5.2",
     "eslint": "^3.16.1",
-    "mkdirp": "^0.5.1",
+    "mkdirp": "^1.0.4",
     "glob-fs": "^0.1.6",
     "nyc": "^10.1.2",
     "rimraf": "^2.6.1",