Include resent headers into civi bulk mail reply function

With the ever increasing nature of DMARC and also SPF its is becoming more important that mail reputation is of vital importance. One of the most obvious issues in terms of mail reputation is the fact that CiviCRM's bulk mailing facility when it is tracking replies it will then send on the reply from the hosts' smtp server. This causes issues as it doesn't inject anything to indicate that it is re-sending this email or similar so the mail client just believes that the email is from the end user. This could potentially mean that the ip address and from address does not match and clients like gmail will start failing messages.