Webmail and Docker

Added a new playbook for Roundcube if you want a webmail, and reworked all of the firewall rules to work with Docker containers. The Roundcube install also uses the managesieve plugin for easy filtering on the server.

• Added roles for Docker and Roundcube, plus a webmail playbook that
  sets up a Roundcube container on a separate machine.

• Reworked firewall to cover both native applications and Docker
  containers. Now blocking in the PREROUTING chain of the "mangle"
  table. This is lower cost because it is early in the process, and
  before the split between INPUT (used by native apps) and FORWARD
  (used by Docker) so it covers both. Also added rules for DHCP
  because connection tracking can break in some situations.

• Reworked fail2ban configuration to allow customization of the jails,
  to change bantimes or retarget to the DOCKER-USER chain.

• Tightened permissions on DKIM folder.

• Added managesieve plugins for Dovecot and Roundcube.

Fine Tuning

[1.1] - 2020-02-18

• Added 'www' user account for uploading website data. Also reworked
  the website configs to add a variety of extra flags.

• Changed '-' to '_' in backup_server and raspberry_pi group names to
  satisfy new Ansible naming requirements. Update your host files and
  group_var files to match. Many lint fixes throughout the playbooks.

• Certbot handling now broken out into a separate role, the renewal
  hooks are now configurable and handled by a few simple variables.
  Now requesting a separate certificate for the mail server. This
  makes it possible to build a mail-only or web-only server without
  having to rework certbot.

• Simplified HTTPS handling, tightened up SLL parameters, and Apache
  directory permissions.

• backup-server play now brings in the cryptdir role. Encryption type
  is 'none' by default, set to luks to encrypt the backups at rest.

• bacula_director_bootstart controls whether director starts at boot.
  Starts normally when encryption type is 'none'.

• mail_services_bootstart controls whether mail starts at boot.
  Starts normally when encryption type is 'none'.

• web_services_bootstart controls whether apache starts at boot.
  Starts normally but can be overridden if using encryption for the
  document root.

• The first.yml playbook now does sudo on raspberry pis.

Initial Baseline

Mail, web, and backup are all functional. I'm sure there are rough edges that could still use attention.