Fixes #2159 - problem with command builder for delete with joins.
add previous exception as param
Fixed error in plural rules handling

Add a rule that is always true if locale has no plural rules defined
fixes #2123
Merge pull request #2163 from odevyatkov/addParentException

add previous exception to base yii exception classes as param
CHANGELOG line for #2163
Merge pull request #2160 branch '2159-fix-delete-with-join' of https://github.com/serebrov/yii into serebrov-2159-fix-delete-with-join

* '2159-fix-delete-with-join' of https://github.com/serebrov/yii:
  Fixes #2159 - problem with command builder for delete with joins.

Conflicts:
	CHANGELOG
some adjustments to pull request #2159
reverted changes of pull request #2163

changes are not compatible with PHP <5.3