树操作：增加、删除、修改、移动

参考示例：增加、删除、修改节点

增加节点

var tree = mini.get("tree1");
var node = tree.getSelectedNode();
var newNode = {};
tree.addNode(newNode, "before", node);

删除节点

var node = tree.getSelectedNode();
tree.removeNode(node);

编辑节点

var node = tree.getSelectedNode();            
tree.beginEdit(node);  

移动节点

tree.moveNode(node, targetNode, "before");