func SimpleProofsFromHashers(items []Hasher) (rootHash []byte, proofs []*SimpleProof) {
	trails, rootSPN := trailsFromHashers(items)
	rootHash = rootSPN.Hash
	proofs = make([]*SimpleProof, len(items))
	for i, trail := range trails {
		proofs[i] = &SimpleProof{
			Aunts: trail.FlattenAunts(),
		}
	}
	return
}
func SimpleProofsFromHashers(items []Hasher) (rootHash []byte, proofs []*SimpleProof) {
	trails, rootSPN := trailsFromHashers(items)
	rootHash = rootSPN.Hash
	proofs = make([]*SimpleProof, len(items))
	for i, trail := range trails {
		proofs[i] = &SimpleProof{
			Aunts: trail.FlattenAunts(),
		}
	}
	return
}
// SimpleProofsFromHashers computes inclusion proof for given items.
// proofs[0] is the proof for items[0].