bug fixes in treegrid remove

[asher]

Hi,
There is a bug in jquery.treegrid.js in function remove (line 630).
After it is called, the html dom element is removed but the parent node's children array still contains the deleted node.
I fixed this bug, which is a mix-up between treeField and idField.
Additionally, in case there are no children left there was the same mix-up, and also the sub-tree of the parent was not removed.
So, here are my fixes:

   /**
    * remove the specified node
    */
   function remove(target, idValue){
      var opts = $.data(target, 'treegrid').options;
      var tr = opts.finder.getTr(target, idValue);
      tr.next('tr.treegrid-tr-tree').remove();
      tr.remove();
      
      var pnode = del(idValue);
      if (pnode){
         if (pnode.children.length == 0){
            //fix - start
            //tr = opts.finder.getTr(target, pnode[opts.treeField]);
            tr = opts.finder.getTr(target, pnode[opts.idField]);
            tr.next('tr.treegrid-tr-tree').remove();
            //fix - end
            var cell = tr.children('td[field=' + opts.treeField + ']').children('div.datagrid-cell');
            cell.find('.tree-icon').removeClass('tree-folder').addClass('tree-file');
            cell.find('.tree-hit').remove();
            $('<span class="tree-indent"></span>').prependTo(cell);
         }
      }
      
      setRowNumbers(target);
      
      /**
       * delete the specified node, return its parent node
       */
      function del(id){
         var cc;
         var pnode = getParent(target, idValue);
         if (pnode){
            cc = pnode.children;
         } else {
            cc = $(target).treegrid('getData');
         }
         for(var i=0; i<cc.length; i++){
            //fix - start
            //if (cc[opts.treeField] == id){
            if (cc[opts.idField] == id){
            //fix - end
               cc.splice(i, 1);
               break;
            }
         }
         return pnode;
      }
   }