Fix sections error

Author: rstacruz

lib/tocify.js

@@ -9,7 +9,7 @@ const tocifyPage = require('./tocify_page')
 module.exports = function tocify (md, files, options) {
   var tokens = marked.lexer(md)
 
-  var re = { sections: {} }
+  var re = { sections: [] }
   var crumbs = [scope]
   var current = re
   var docs = options && options.docs || 'docs'