(IcingaWeb2) Move configuration (user preferences) backend from INI
files to a dedicated pgSQL db.

- (Icinga2) Preseed correctly all the debconf variables to have IDO db created
  and populated by `icinga2-ido-pgsql` deb installation script.

- (IcingaWeb2) Use a different user, `www-data`, with lower
  privileges, to access the IDO db in read-only mode.

- Use everywhere socket (local ident) authentication to PostgreSQL to
  avoid local service password.

(IcingaWeb2) Configuration issues fixed:

- Missing `php-fpm` requirement.

- Migrating php7.0 -> php 7.3 in nginx config location config file.

- Fixed `rewrite` rule in nginx configuration:
    When usign `/icingaweb2` as rewrite target nginx automatically
    expand the redirect 302 response as
    `$scheme://$remote_host:$remote_port/icingaweb2`, causing
    connection to fail when behind a *reverse proxy*, because
    remote_post and remote_host are incorrect.

- Remove hardcoded `status.lilik.it` in `meta/main.yaml`,
  `server_fqdn` is already defined in `defaults/main.yaml` as
  `{{ ansible_hostname }}.{{ domain }}`.

(IcingaWeb2) LDAP:

- procedure to automatically issue service credetinals to authenticate
  with the ldap server.

- starttls secured ldap connection with service account.

- use of the variable `base_dn` instead of hard-coded values in config
  files.

(IcingaWeb2) CONFIGURATION:

- fixed rsync parameters.

- resource renaming.

- remove the handling of which template to use
- do not access parent role
- update riot-web nginx configuration
- update icinga role to use new nginx templating
- update synapse nginx configuration
- update matrix role to use new nginx templates
- update dokuwiki to use new nginx template
- extend nginx template in dokuwiki
- update login role to new nginx templates
- add protocol for default option
- add extra block to nginx template
- update riote-web version
- fix template extension for riot web nginx definition
- update login template for nginx endpoint