Fails to check DMARC policy if there is no MX record #16
Description
The script skips checking for DMARC, and possibly other policies, if there is no MX record.
This could be considered a bug, however the script does say #N/A rather than None.
This default of not checking should be highlighted to users. If possible consider adding an option to force checking of specific / all policies, regardless of MX records.
To recreate the issue run the script against any domain that has a DMARC policy but no MX record.
The domain this was noticed for was coronavirus.gov, see https://internet.nl/mail/coronavirus.gov/399588/.
