Fixed the scrict warning.. 

Fixed following strict warnings

Strict (2048): Declaration of SluggableBehavior::setup() should be compatible with ModelBehavior::setup(Model $model, $config = Array) [APP\Model\Behavior\SluggableBehavior.php, line 23]

Strict (2048): Declaration of SluggableBehavior::beforeSave() should be compatible with ModelBehavior::beforeSave(Model $model) [APP\Model\Behavior\SluggableBehavior.php, line 23]