code: func (extr *ContentExtractor) updateScore(node *goquery.Selection, addToScore int) {
  	currentScore := 0
  	var err error
  	scoreString, _ := node.Attr("gravityScore")
  	if scoreString != "" {
  		currentScore, err = strconv.Atoi(scoreString)
  		if err != nil {
  			currentScore = 0
  		}
  	}
  	newScore := currentScore + addToScore
  	extr.config.parser.setAttr(node, "gravityScore", strconv.Itoa(newScore))
  }
docs: //adds a score to the gravityScore Attribute we put on divs
  //we'll get the current score then add the score we're passing in to the current