Elementary/naviframe - doc more. 
Elementary/naviframe - doc more. 

Since the users have no idea about elm_object_item content/text parts names which are available,
added those part names in doc here. 



SVN revision: 63485

tasn/elementary,FlorentRevest/Elementary,tasn/elementary,rvandegrift/elementary,rvandegrift/elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,rvandegrift/elementary,tasn/elementary,FlorentRevest/Elementary,tasn/elementary,FlorentRevest/Elementary