correct annotations

app/models/post.rb

@@ -554,8 +554,8 @@ end
 #  post_number             :integer          not null
 #  raw                     :text             not null
 #  cooked                  :text             not null
-#  created_at              :datetime
-#  updated_at              :datetime
+#  created_at              :datetime         not null
+#  updated_at              :datetime         not null
 #  reply_to_post_number    :integer
 #  reply_count             :integer          default(0), not null
 #  quote_count             :integer          default(0), not null

app/models/site_setting.rb

@@ -103,6 +103,6 @@ end
 #  name       :string(255)      not null
 #  data_type  :integer          not null
 #  value      :text
-#  created_at :datetime
-#  updated_at :datetime
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
 #