Merge pull request #24 from datesss/master

key to string to string before converting

Author: woodyrew

lib/index.js

@@ -46,7 +46,7 @@ function plugin(options){
         data.contents = new Buffer(str);
       }
       keys.forEach(function(key) {
-        data[key] = marked(data[key], options);
+        data[key] = marked(data[key].toString(), options);
       });
 
       delete files[file];