Revert "structure changes"

This reverts commit 1316be6b2bee3488b2c6732a84029e7876867825.
Revert "treeviewX host element"

This reverts commit db75f2e77a8e777554d4ffa2b99304b27c153e3f.
Revert "treeviewX"

This reverts commit 6394ba19643df437906c49990a82815eb4ead1e9.
Revert "new file:   TagPan/TreeViewX.xaml"

This reverts commit be026ff1049b4e7c0dc48864af264193a14277e3.