Leave package mkdirp only in production dependencies

Author: dgolovin

package.json

@@ -43,6 +43,7 @@
     "humanize": "0.0.9",
     "humanize-duration": "3.10.0",
     "mkdirp": "0.5.1",
+    "openpgp": "^2.5.8",
     "patternfly": "3.25.1",
     "pify": "3.0.0",
     "replace-in-file": "2.5.3",
@@ -83,7 +84,6 @@
     "jsdom": "11.1.0",
     "merge-stream": "1.0.1",
     "minimatch": "3.0.4",
-    "mkdirp": "0.5.1",
     "mocha": "3.4.2",
     "mock-fs": "4.4.1",
     "npm-check-updates": "2.12.1",