Remove IPv6 address of dgoulet's default bridge
The default bridge CDF2E852BF539B82BD10E27E9115A31734E378C2
has both an IPv4 and an IPv6 address but isn't reachable over IPv6. David says that he migrated to a new host a while ago, and this new host doesn't have IPv6. Let's remove the IPv6 address of this bridge. I'll push patches in a minute.