Phase 1 of migrating APPR-specific tables to tables with the Appr prefix

Fixes https://jira.coreos.com/browse/QUAY-950

util/config/database.py

@@ -1,4 +1,6 @@
-from data import model, appr_model
+from data import model
+from data.appr_model import blob
+from data.appr_model.models import OLD_MODELS
 
 
 def sync_database_with_config(config):
@@ -7,4 +9,4 @@ def sync_database_with_config(config):
   location_names = config.get('DISTRIBUTED_STORAGE_CONFIG', {}).keys()
   if location_names:
     model.image.ensure_image_locations(*location_names)
-    appr_model.blob.ensure_blob_locations(*location_names)
+    blob.ensure_blob_locations(OLD_MODELS, *location_names)

util/config/schema.py

@@ -881,6 +881,13 @@ CONFIG_SCHEMA = {
       'x-example': False,
     },
 
+    # Feature Flag: Read only app registry.
+    'FEATURE_READONLY_APP_REGISTRY': {
+      'type': 'boolean',
+      'description': 'Whether to App repositories are read-only. Defaults to False',
+      'x-example': True,
+    },
+
     # Feature Flag: Public Reposiotires in _catalog Endpoint.
     'FEATURE_PUBLIC_CATALOG': {
       'type': 'boolean',