Changes some properties to be readonly instead of strong
Changes some properties to be readonly instead of strong

jonesgithub/DZNPhotoPickerController,taojack/DZNPhotoPickerController,ahbou/DZNPhotoPickerController,imjerrybao/DZNPhotoPickerController,taojack/DZNPhotoPickerController,dzenbot/DZNPhotoPickerController,taojack/DZNPhotoPickerController,dennislysenko/DZNPhotoPickerController,lichuanjun/DZNPhotoPickerController,topfreegames/TFGPhotoPickerController,jonesgithub/DZNPhotoPickerController,jonesgithub/DZNPhotoPickerController,imjerrybao/DZNPhotoPickerController,dredenba/DZNPhotoPickerController,imjerrybao/DZNPhotoPickerController,ndnguru/DZNPhotoPickerController,taojack/DZNPhotoPickerController,jonesgithub/DZNPhotoPickerController,imjerrybao/DZNPhotoPickerController