Fixes #1796: separate count criteria in CActiveDataProvider.
Proper docstring for CActiveDataProvider::$_criteria and CActiveDataProvider::$_countCriteria.
Merge branch 'master' of github.com:yiisoft/yii into fixes-1796-CActiveDataProvider-countCriteria
Merge pull request #2392 from resurtm/fixes-1796-CActiveDataProvider-countCriteria

Fixes #1796: separate count criteria in CActiveDataProvider.