* refactor: create log.Infof and log.Warnf * refactor: review DNS providers. - use one `http.Client` by provider instead of one client by request - use the same receiver name `d` for all `DNSProvider` - use `http.MethodXXX` * refactor: logger init.
* refactor: review DNS providers.
* Add DNS Provider for CloudXNS * Fix package path error * Fix typo CloudFlare -> CloudXNS * Fix typo makeReauest -> makeRequest * Change http.Client to acme.HTTPClient
