code: func (h *Histogram) CumulativeDistribution() []Bracket {
  	var result []Bracket
  
  	i := h.pIterator(1)
  	for i.next() {
  		result = append(result, Bracket{
  			Quantile: i.percentile,
  			Count:    i.countToIdx,
  			ValueAt:  i.highestEquivalentValue,
  		})
  	}
  
  	return result
  }
docs: // CumulativeDistribution returns an ordered list of brackets of the
  // distribution of recorded values.