fix(package): update fs-extra to version 5.0.0 (#661)

Author: greenkeeper[bot]

package.json

@@ -37,7 +37,7 @@
     "@types/marked": "0.3.0",
     "@types/minimatch": "2.0.29",
     "@types/shelljs": "0.7.0",
-    "fs-extra": "^4.0.0",
+    "fs-extra": "^5.0.0",
     "handlebars": "^4.0.6",
     "highlight.js": "^9.0.0",
     "lodash": "^4.13.1",