TemplateTool: upgrader first removes deprecated BT and then upgrade all BT
For example, if property_sheet "prop" was moved from BT 1 to BT 2 and BT 1 doesn't exist anymore.
Before this commit we have this order:
- install BT 2 ("prop" exist and isn't touched)
- remove BT 1 ("prop" is removed) => at the end "prop" doesn't exist anymore
After this commit we have this order:
- remove BT 1 ("prop" is removed)
- install BT 2 ("prop" is readded) => at the end "prop" exists and is OK