public <T> Bufferable<T> readFrom(String name, Iterable<T> iterable) {
      Iterator<T> iter = iterable.iterator();
      return fromGenerator(name, next -> {
        while (iter.hasNext()) {
          next.accept(iter.next());
        }
      }, 1);
    }
Adds an initial step that reads all items from {@code iterable} in a single worker thread to produce items for
this queue.
planetiler-core/src/main/java/com/onthegomap/planetiler/worker/WorkerPipeline.java