78d4ff4bb7
see: https://lists.gnupg.org/pipermail/gnupg-announce/2018q2/000425.html http://seclists.org/oss-sec/2018/q2/169
REQUIREMENTS
GnuPG requires a sendmail compatibility link '/usr/sbin/sendmail'. Be
sure that you have installed one of the following:
- esmtp
- masqmail
- postfix
- sendmail
- msmtp
- exim
PRE-INSTALL
POST-INSTALL
PRECAUTION