chore(package): update fs-extra to version 8.0.1

Closes #24

Author: greenkeeper[bot]

package.json

@@ -34,7 +34,7 @@
     "yeoman-generator": "^1.1.1"
   },
   "devDependencies": {
-    "fs-extra": "^2.1.2",
+    "fs-extra": "^8.0.1",
     "jshint": "^2.8.0",
     "mocha": "^3.2.0",
     "yeoman-test": "^1.6.0",