func (dao *LogIndexRiakDAO) GetLogIndex(userId string) (ent.TimelineIndex, error) {
	index := ent.TimelineIndex{}
	responce := dao.fetch(userId)
	if responce == nil || responce.IsNotFound {
		return index, nil
	}
	if err := json.Unmarshal(responce.Values[0].Value, &index); err != nil {
		return nil, err
	}
	index = ent.SortEntries(index)
	return index, nil
}
func (dao *LogIndexRiakDAO) AppendToLogIndex(userId string, entry ent.IndexEntry) error {
	value := riak.Object{}
	value.ContentType = "application/json"
	value.Charset = "utf-8"
	value.ContentEncoding = "utf-8"
	index := ent.TimelineIndex{entry}
	if responce := dao.fetch(userId); responce != nil && !responce.IsNotFound {
		value.VClock = responce.VClock
		if err := json.Unmarshal(responce.Values[0].Value, &index); err != nil {
			return err
		}
	}
	index = ent.SortEntries(append(index, entry))
	encoded, _ := json.Marshal(index)
	value.Value = encoded
	return dao.store(userId, value)
}