chris barr's touchscroll goes tweening

    document.getElementById(id).addEventListener("touchstart", function(event) {
      var tween = require("lib/tween");
      tween.objects = []; // reset tween?
      scrollStartPos  = this.scrollTop+event.touches[0].pageY;
      this.scrollLast = event.touches[0].pageY;
      event.preventDefault();
    },false);

    document.getElementById(id).addEventListener("touchmove", function(event) {
      this.scrollSpeed     = (event.touches[0].pageY-this.scrollLast);
      this.scrollTop       = scrollStartPos-event.touches[0].pageY;
      this.scrollLast      = event.touches[0].pageY;
      event.preventDefault();
    },false);

    document.getElementById(id).addEventListener("touchend", function(event) {
      var tween = require("lib/tween");
      this.scrollTweening  = true;
      tween.addTween( this, {
        time: 1.0,
        transition: 'easeOutQuint',
        onComplete: function(){ },
        scrollTop: this.scrollTop - (this.scrollSpeed*2)
      });
      event.preventDefault();
    },false);