Add migration for unique subnets.
dns: force dns records to lower case (PostgreSQL already enforces this).
Overwrite old PTR when saving IP address.
IPAddress: allow interface name to be multiple labels.
IPAddress: IP address must be unique.
Reorganize host table.
Allow single-character hostnames.
IPAddress: add admin.
Sort Hosts by reverse domain.
IPAddressField: support default lookup types.
Fix IPAddress foreign key bug by making Create Host two-step process.
IPAddress: add 'primary' field that creates CNAME.
IPAddress: validate that only one ip address per host is primary.