Some mistakes about 05-basic-dom-node-properties/2-tree-info

[en.javascript.info](https://github.com/javascript-tutorial/en.javascript.info)/[2-ui](https://github.com/javascript-tutorial/en.javascript.info/tree/master/2-ui)/[1-document](https://github.com/javascript-tutorial/en.javascript.info/tree/master/2-ui/1-document)/[05-basic-dom-node-properties](https://github.com/javascript-tutorial/en.javascript.info/tree/master/2-ui/1-document/05-basic-dom-node-properties/2-tree-info/)

1. Rename 2-tree-info to 1-tree-info

Reason: 2-tree-info is first task

2. Using external js instead of inline js

Reason: js will execute before brower finish HTML loading. It's inconvenient for user to count \

Start in 2-ui/1-document/05-basic-dom-node-properties/2-tree-info and inspect the task files and their inline JavaScript. Confirm the directory numbering and how the example currently loads JavaScript; done means the task is under the requested name and its JavaScript is external without disrupting the exercise.

Written by the indexing model from the issue text.