Adding daily mail review from Issue 839 (#881)

* Added dependencies, binary, startup configuration
* Added env variable to dist files/readme
* send summary after each logrotate, added env variable for mail/logrotate interval
* remove mail.log from rsyslogs logrotate
* rotate mail.log when no email is set
* Added documentation for POSTFIX_LOGROTATE_INTERVAL
* Removed interval option, since its not being tested for.
* changed test to force logrotate to rotate fixed logrotate config
* readded setup_environment, made logrotate_setup being called everytime
* changed documentation for new variable names - again
* Did Documentation, added a default recipient, added test for default config.
* layout fix
* changed variable names apposite the documentation

Dockerfile

@@ -50,6 +50,7 @@ RUN apt-get update -q --fix-missing && \
     opendkim-tools \
     opendmarc \
     pax \
+    pflogsumm \
     p7zip-full \
     postfix-ldap \
     postfix-pcre \
@@ -197,6 +198,7 @@ RUN sed -i -r "/^#?compress/c\compress\ncopytruncate" /etc/logrotate.conf && \
   sed -i -r 's|UpdateLogFile /var/log/clamav/|UpdateLogFile /var/log/mail/|g' /etc/clamav/freshclam.conf && \
   sed -i -r 's|/var/log/clamav|/var/log/mail|g' /etc/logrotate.d/clamav-daemon && \
   sed -i -r 's|/var/log/clamav|/var/log/mail|g' /etc/logrotate.d/clamav-freshclam && \
+  sed -i -r '/\/var\/log\/mail\/mail.log/d' /etc/logrotate.d/rsyslog && \
   sed -i -r 's|/var/log/mail|/var/log/mail/mail|g' /etc/logrotate.d/rsyslog && \
   # prevent syslog logrotate warnings \
   sed -i -e 's/\(printerror "could not determine current runlevel"\)/#\1/' /usr/sbin/invoke-rc.d && \