Add back Cache::engine() as deprecated alias for Cache::pool().
Add back Cache::engine() as deprecated alias for Cache::pool().

dakota/cakephp,ADmad/cakephp,ndm2/cakephp,CakeDC/cakephp,cakephp/cakephp,ADmad/cakephp,ADmad/cakephp,ndm2/cakephp,cakephp/cakephp,CakeDC/cakephp,dakota/cakephp,CakeDC/cakephp,CakeDC/cakephp,dakota/cakephp,cakephp/cakephp,cakephp/cakephp,ADmad/cakephp,ndm2/cakephp,dakota/cakephp,ndm2/cakephp