added cached columns for post update count, post upload count, note update count, favorite count to users; fixed tests

app/models/user.rb

@@ -182,12 +182,14 @@ class User < ActiveRecord::Base
     def add_favorite!(post)
       return if Favorite.exists?(:user_id => id, :post_id => post.id)
       Favorite.create(:user_id => id, :post_id => post.id)
+      increment!(:favorite_count)
       post.add_favorite!(self)
     end
     
     def remove_favorite!(post)
       return unless Favorite.exists?(:user_id => id, :post_id => post.id)
       Favorite.destroy_all(:user_id => id, :post_id => post.id)
+      decrement!(:favorite_count)
       post.remove_favorite!(self)
     end
   end