remove race condition where c3nav tried to load a wrong router

src/c3nav/mapdata/models/update.py

@@ -176,7 +176,7 @@ class MapUpdate(models.Model):
             from c3nav.routing.locator import Locator
             Locator.rebuild(new_updates[-1].to_tuple)
 
-            for new_update in new_updates:
+            for new_update in reversed(new_updates):
                 new_update.processed = True
                 new_update.save()