Implemented configuration option to skip deletion of the cloudinary resource on destory

We've come into the problem that when using multiple installations of a rails app "dev/test/prod" it might be very dangerous if anybody deletes models in the development system. As attachinary destroys it's resources on cloudinary, this might lead to missing images in production.

As solution, I've implemented a configuration option to skip deletion of the cloudinary resource.

    # will only destroy cloudinary resources in production
    has_attachment :video, accept: [:jpg], delete_resource_on_destroy: Rails.env.production?