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.
Because it might be logged to a file, or wherever.  This is immune to changes elsewhere.  Adding handlers is normal.