Certificate permissions for etherpad

src/freedombone-app-etherpad

     if [ -f /etc/ssl/private/${ETHERPAD_DOMAIN_NAME}.key ]; then
         chown etherpad: /etc/ssl/private/${ETHERPAD_DOMAIN_NAME}.key
     fi
+    usermod -a -G ssl-cert etherpad
 
     # Ensure that the database gets backed up locally, if remote
     # backups are not being used