Revert "Initial implement"

This reverts commit 9f3941ae76cc6f80275fa7688d753b4ae63af5ad.
Revert "Revert "Initial implement""

This reverts commit dadd815ffa6aed9a33aa80b252cd038b16fa122f.
Upload, download, update DOM

Upload XML, save (or download) XML.
After double click, DOM and resultant XML are updated.