Remove Security.cipherSeed.
Remove Security.cipherSeed.

It is no longer used in CakePHP core and should be removed.


	See: cakephp/cakephp@3ba064a0cce0e5dd6648b721451b1d81de57e82e


makallio85/fish-diary,makallio85/fish-diary,QoboLtd/project-template-cakephp,ojengwa/cake-appengine,QoboLtd/project-template-cakephp,QoboLtd/project-template-cakephp,ojengwa/cake-appengine,QoboLtd/project-template-cakephp,makallio85/fish-diary,QoboLtd/project-template-cakephp