Email capabilities (mailutils+postfix) are required for 
certificate managers and optional for clients.

Email ALARM (lib/asceds-utils: asceds-mailto-alarm):

If ${ALARM} is empty, no email will be sent.
Email messages are sent to the ALARM address (admin or ticketing system) if:
a. if expired cert 
      cert_manager: asceds-propagate-certbot --> asceds-expiration-test
      local:        asceds-service-reconfig  --> asceds-expiration-test              
b. systems with noreturn policy (ro like pi-kvm) --> asceds-propagate-certbot
c. cert files cannot be moved (network or ssh access problems) --> asceds-send-cert 
d. TBI (not sure if needed) if errors --> create digest

Email messages are sent to the requestor (all from the certificate manager):
   * NO_ASCEDS in cert.conf file
   * REQUESTED_BY in web request file
if:
a. revoked certificate for unmanaged client
       asceds-web-unmanaged -r --> if running the queue (not with -c)
b. generate/renew certificate for unmanaged client
       asceds-web-unmanaged -n --> if running the queue (not with -c)
c. certificate was automatically renewed ny certbot for unmanaged client
       asceds-propagate-certbot --> for unmanaged clients
d. certificate was generated/renewed through the website request 
   for managed client
       asceds-web-propagate --> if running the queue (not with -c)
