Retain zone file comments

Hi,

I didn't see any other issue for this, so I opened anew one. Although I can't believe this hasn't been requested already.

Please retain comments in the zone file. At least in the zone data section (as opposed to DNSSEC signatures and NSEC/3).

Reasoning:

I want to move email providers. So I have to insert new dane records and new dkim records, but I can't just remove the old ones. They both have to be in the zone file for some time. When I get back to the file, all my comments are gone and it is really hard to see what are the new and what are the old records. Whould be much easier with some comments.

Same goes for these pesky authorization TXT records. Some have the service name in it, but some do not. A comment would do wonders once I need to remove a service.