Add ability to use nested only parameter

- The only string works much the same as before with its comma separation
-- Nested includes are indicated with square brackets "[ ]"
-- The nested include is the value immediately preceding the square brackets
-- The only string is the comma separated string inside those brackets
- Default includes are split between format types when necessary
-- This prevents unnecessary includes from being added on page load
- Available includes are those items which are allowed to be accessible to the user
-- Some aren't because they are sensitive, such as the creator of a flag
-- Some aren't because the number of associated items is too large
- The amount of times the same model can be included to prevent recursions
-- One exception is the root model may include the same model once
--- e.g. the user model can include the inviter which is also the user model
-- Another exception is if the include is a has_many association
--- e.g. artist urls can include the artist, and then artist urls again

app/controllers/posts_controller.rb

@@ -11,7 +11,7 @@ class PostsController < ApplicationController
       end
     else
       @post_set = PostSets::Post.new(tag_query, params[:page], params[:limit], raw: params[:raw], random: params[:random], format: params[:format])
-      @posts = @post_set.posts
+      @posts = @post_set.posts = @post_set.posts.includes(model_includes(params)) if !@post_set.is_random?
       respond_with(@posts) do |format|
         format.atom
       end
@@ -96,6 +96,14 @@ class PostsController < ApplicationController
 
   private
 
+  def default_includes(params)
+    if ["json", "xml", "atom"].include?(params[:format])
+      [:uploader]
+    else
+      (CurrentUser.user.is_moderator? ? [:uploader] : [])
+    end
+  end
+
   def tag_query
     params[:tags] || (params[:post] && params[:post][:tags])
   end