upgrade to cakePHP 1.3.17 #363

we have two unit tests with errors
section.test.php and version.test.php
see https://github.com/bedita/bedita/issues/363#issuecomment-17475346 for more detail
fix contain definition on BEObject, close #363

in BEObject::beforeValidate() there was "contain" => ("") instead of "contain" => array()
Merge local branch 'issue/363-upgrade-cakephp-1.3.17'