how to build a virtual dom tree

如何實現一個Virtual DOM算法

https://github.com/livoras/blog/issues/13

1. use javascript object to present the structure of dom, and use it to build a real dom tree, then insert to document
2. when state updated, recreate a object tree, and then compare old tree and new tree, and record the diff
3. use 2.) diff to 1.) real dom tree

2.1. how to compare:

1.Depth-first search for new and old tree, and add unique mark

2.diff type: REPLACE, REORDER, PROPS, TEXT

3.compare list: ex => abcdefghi =>abchdfgij