Put sorting in web_link, page_context and design

app/models/design/design.rb

@@ -3,10 +3,10 @@ class Design
   include Mongoid::Timestamps
   include ParserLayout
 
-  field :title
-  field :author
-  field :intro
-  field :version
+  field :title, :type => String
+  field :author, :type => String
+  field :intro, :type => String
+  field :version, :type => String
 
   has_many :pages