fix(package): update marked to version 0.6.3

Closes #19

Author: greenkeeper[bot]

package.json

@@ -31,7 +31,7 @@
     "ember-cli-babel": "^6.16.0",
     "front-matter": "2.3.0",
     "glob": "7.1.3",
-    "marked": "0.5.0",
+    "marked": "0.6.3",
     "rss": "^1.2.2"
   },
   "devDependencies": {