Implement V2 interfaces and remaining V1 interfaces

Also adds some tests to registry tests for V1 stuff.
Note: All *registry* tests currently pass, but as verbs are not yet converted, the verb tests in registry_tests.py currently fail.

endpoints/v1/registry.py

@@ -14,7 +14,7 @@ from auth.permissions import (ReadRepositoryPermission,
                               ModifyRepositoryPermission)
 from auth.registry_jwt_auth import get_granted_username
 from data import model, database
-from data.model import v1
+from data.interfaces import v1
 from digest import checksums
 from endpoints.v1 import v1_bp
 from endpoints.decorators import anon_protect