Move all order logic to models

- Have a default order for each model
-- The overall default is ID DESC
- Allow for custom orderings
-- When comma-separated IDs are used

app/controllers/forum_posts_controller.rb

@@ -25,7 +25,7 @@ class ForumPostsController < ApplicationController
 
   def index
     @query = ForumPost.search(params[:search])
-    @forum_posts = @query.includes(:topic).order("forum_posts.id DESC").paginate(params[:page], :limit => params[:limit], :search_count => params[:search])
+    @forum_posts = @query.includes(:topic).paginate(params[:page], :limit => params[:limit], :search_count => params[:search])
     respond_with(@forum_posts) do |format|
       format.xml do
         render :xml => @forum_posts.to_xml(:root => "forum-posts")