---
features:
  - Adds ``neutron-vpnaas`` API definitions to neutron-lib, including
    ``vpnaas``, ``vpn-endpoint-groups`` and ``vpn-flavors``.
  - Migrate user facing exceptions into neutron-lib along with the API
    definitions.
  - A new validator for type ``type:list_of_subnets_or_none`` to validate
    data is a list of subnet dicts or ``None`` is added too.