Fix E402 (module level import not at top of file) pep8 errors
and no longer ignore new failures.
Trivialfix
Change-Id: If9a202f1f322b5b03966c692e33e94b7c872079b
Adds an ip_version field for enforcing an address family on
an AddressScope. All SubnetPools in an AddressScope must be
from the same address family. A SubnetPool cannot be created
in an AddressScope with a different address family.
Change-Id: Ibc6de08e0ef58a5da954d13f274f6003012a76cd
Partially-Implements: blueprint address-scopes