Feature request: ttl for DNS module

[zerkms]

My workflow to switch TTL for RRs is usually the following:

1. Decrease it to 1m
2. Wait for previous TTL interval til everybody has their dns cache refreshed with a low TTL
3. Update to a new value with the same small TTL of 1m
4. If all is good - bump TTL back to a higher value (eg 30m)

As one may see - it's simple to overlook the step 4 and have it running with an unreasonable low TTL.

If DNS module exported the TTL value I could have created an alert.

If the core team thinks the community would benefit for having it and that the PR would be accepted - I'll happily implement it.