feat(fusiondirectory-setup) Add option to remove supann root

New options removes the establishement node stored under root in
 previous version as this is not what SupAnn recommends.
People migrating from FD<1.4 will need to run
 fusiondirectory-setup --remove-supann-root
 and then in FusionDirectory open the root establishment and check the
 "Root establishment" checkbox again. (The other order should work too)

issue #6062