Fix too much recursion error during update_location_tree...

Fix too much recursion error during update_location_tree. Don't traverse descendents during the all-locations update. Actually disable update_location_tree during prepopulate.

Had to split off disabling the location tree update from auth.override, as they were at cross purposes elsewhere.
True, so maybe this should become a method in current.log then...seems useful for testing (and we wouldn't want to repeat it).