code: @Beta
    public static void copy(File from, OutputStream to) throws IOException {
      asByteSource(from).copyTo(to);
    }
docs: Copies all bytes from a file to an output stream.
  
  <p><b>{@link java.nio.file.Path} equivalent:</b> {@link
  java.nio.file.Files#copy(java.nio.file.Path, OutputStream)}.
  
  @param from the source file
  @param to the output stream
  @throws IOException if an I/O error occurs