Add ds_record to outputs

[joe-niland]

what

• Include DS record for each zone in outputs

• Output will be like this:

   {
       "ds_record" = {
         "prod.example.com" = "..."
       }
       "key_arn" = "arn:aws:kms:..."
       "this_key_arn" = "arn:aws:kms:..."
   }

why

• This was needed by one of our modules to add the DS record for a delegated zone to the primary to create a chain of trust

references

• None

[joe-niland]

Hi @jbouse
I was wondering if you could take a look at this PR?
The auto-format job seems to have an issue.