code: func NewIndexedIterator(index IteratorIndexer, strict bool) Iterator {
  	return &indexedIterator{index: index, strict: strict}
  }
docs: // NewIndexedIterator returns an 'indexed iterator'. An index is iterator
  // that returns another iterator, a 'data iterator'. A 'data iterator' is the
  // iterator that contains actual key/value pairs.
  //
  // If strict is true the any 'corruption errors' (i.e errors.IsCorrupted(err) == true)
  // won't be ignored and will halt 'indexed iterator', otherwise the iterator will
  // continue to the next 'data iterator'. Corruption on 'index iterator' will not be
  // ignored and will halt the iterator.