code: function(ul) {
      var prevLevel = {level: -1, index: -1, parent: -1, val: ''};
      var levelParent = {0: -1};
      tocList = ul.children("li");
      tocList.each(function(i) {
        var me = $(this).removeClass("toc-active");
        var currentLevel = parseInt(me.attr('class').trim().slice(-1));
        if (currentLevel > prevLevel.level) {
          currentParent = prevLevel.index;
        } else if (currentLevel == prevLevel.level) {
          currentParent = prevLevel.parent;
        } else if (currentLevel < prevLevel.level) {
          currentParent = levelParent[currentLevel] || prevLevel.parent;
        }
        levelParent[currentLevel] = currentParent;
        var currentVal = $('a', this).text().trim().toLowerCase();
        treeObject[i] = {
          val: currentVal,
          level: currentLevel,
          parent: currentParent
        }
        prevLevel = {index: i, val: currentVal, level: currentLevel, parent: currentParent};
      });
    }
docs: Create the tree