code: @Override
    public <T> BulkFuture<Map<String, T>> asyncGetBulk(Transcoder<T> tc,
        String... keys) {
      return asyncGetBulk(Arrays.asList(keys), tc);
    }
docs: Varargs wrapper for asynchronous bulk gets.
  
  @param <T>
  @param tc the transcoder to serialize and unserialize value
  @param keys one more more keys to get
  @return the future values of those keys
  @throws IllegalStateException in the rare circumstance where queue is too
  full to accept any more requests