Document a checklist of things that make a new provider "complete". I can think of a few things.

1. Write the provider itself (either Registrar, DnsProvider, or bot)
2. Add the provider to https://stackexchange.github.io/dnscontrol/provider-list
3. Add the provider to the bullet list on https://github.com/StackExchange/dnscontrol