[cert-management]

Improvements

[OPERATOR] If a DNS nameserver for prechecking DNS propagation are not reachable by UDP, (#18, @MartinWeindel)
- the DNS query request is retried with TCP.
[OPERATOR] The DNS nameservers for prechecking can be specified by command line option (#18, @MartinWeindel)
- --precheck-nameservers
[OPERATOR] Added command line option --precheck-additional-wait to wait for last mile record (#18, @MartinWeindel)
- propagation to the DNS server used by the ACME server
[OPERATOR] Add missing translation from helm values file to controller arguments for 'dns-class' and 'issuer.dns-class' arguments. (#17, @Diaphteiros)
[OPERATOR] new command line option --dns-class to set the dns class for challenging dns entries optionally (#16, @MartinWeindel)