Sam Hemelryk authored May 11, 2011 and Eloy Lafuente committed May 23, 2011

* Added the component and ratingarea fields and implemented it throughout
  the rating API as mandatory fields
* Cleanup rating indexes
* Upgrade forum/data/glossary ratings
* Moved the logic in the render_rating method to methods of the rating object.
* Added new callback for checking ratingareas
* Cleaned comments here and there
* Mark the xxx_get_participants methods as deprecated
* Refactor rate_ajax and ratingsuser_can_view_aggregate methods
* Cleaned up rating/index.php to use html_table object and moved inline styles to CSS.
* Added missing properties of the rating object that were being set throughout the rating
  API.