Simplifying queries around images and placements

Only verbs needs to load placements for multiple images, so we can vastly simplify and optimize most queries by making it two-step, and having the rest of the image loads not worry about placements

initdb.py

@@ -584,7 +584,7 @@ def populate_database(minimal=False, with_storage=False):
                         'Complex repository with many branches and tags.',
                         False, [(new_user_2, 'read'), (dtrobot[0], 'read')],
                         (2, [(3, [], 'v2.0'),
-                             (1, [(1, [(1, [], ['prod'])],
+                             (1, [(1, [(2, [], ['prod'])],
                                    'staging'),
                                   (1, [], None)], None)], None))