code: public static <T> Maybe<T> allOf(Maybe<T>... fts) {
  
          return Single.fromPublisher(Future.allOf(futures(fts))).toMaybe();
      }
docs: Wait until all the provided Future's to complete
  
  @see CompletableFuture#allOf(CompletableFuture...)
  
  @param fts Maybes to  wait on
  @return Maybe that completes when all the provided Futures Complete. Empty Future result, or holds an Exception
  from a provided Future that failed.