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

[lb-fes]

en.javascript.info/2-ui/1-document/05-basic-dom-node-properties

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 <li>.