'Cache an image with supplied iterator.
:param image_id: Image ID
:param image_file: Iterator retrieving image chunks
:param image_checksum: Checksum of image
:returns: True if image file was cached, False otherwise'

def cache_image_iter(self, image_id, image_iter, image_checksum=None):

    if (not self.driver.is_cacheable(image_id)):
        return False
    for chunk in self.get_caching_iter(image_id, image_checksum, image_iter):
        pass
    return True
