Creating a registrar module

Implement domain registration and management methods.

modules/registrars/acmereg/acmereg.php defines AcmeregRegistrar. Add its settings metadata to the registrar registry.

Method	Purpose
`testConnection`	Validate credentials.
`registerDomain`	Register 1–10 years with nameservers.
`transferDomain`	Transfer with EPP/auth code.
`renewDomain`	Renew idempotently.
`get/saveNameservers`	Manage authoritative nameservers.
`get/saveRegistrarLock`	Manage transfer lock.
`getEppCode`	Retrieve authorization code.
`get/saveDnsRecords`	Optional DNS management.
`get/saveWhoisContacts`	Optional contact management.

Return normalized arrays. Never log auth codes or credentials. Validate domains, periods, nameservers and record types before provider calls.