def download_blob_to(file) #:doc:
        file.binmode
        blob.download { |chunk| file.write(chunk) }
        file.flush
        file.rewind
      end
def download_blob_to(file) #:doc:
        file.binmode
        blob.download { |chunk| file.write(chunk) }
        file.flush
        file.rewind
      end
Efficiently downloads blob data into the given file.