Revert "XWIKI-9480: "Upgrade all wikis" option does not work"

This reverts commit 971f15520602bfd0a9324fc9ff71eff97d77c4e6.
XWIKI-9480: "Upgrade all wikis" option does not work
XWIKI-9480: "Upgrade all wikis" option does not work
* add new step
XWIKI-9480: "Upgrade all wikis" option does not work
XWIKI-9480: "Upgrade all wikis" option does not work
XWIKI-9480: "Upgrade all wikis" option does not work
* try to use current namespace when executing steps transformations
XWIKI-9480: "Upgrade all wikis" option does not work
* allow the script to set the transformation id
XWIKI-9492: "Upgrade all wikis" feature does not support ExtensionUI Id renaming
* Add a new step called "Wikis" that lists the existing wikis with the recommended UI that needs to be installed.
* Fix the way extension.vm is included by distribution.vm (#parse has some problems when multiple requests are made).
Merge branch 'feature-upgradeall'