[#29864] Many properties missing when triggering onContentPrepare

Joomla! Content (com_content) views "Featured" and "Category," when the system triggers onContentPrepare, provide only intro text.
But many "Content Plugins" need more than the intro text. So I made a few changes, and now the system provides full object.

Here you are a link to the record on Joomla! code tracker.
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=29864