- Coherent quotation style
    Single quotes for text variable (even if implicit), no quotes for
    variable and conditional statements, if not required.

- Some useful tags added:
  * ssh_certs
	  renewal of server SSH certificates and configuration of authorized
      CA.
  * tls_pub
	  renewal of public TLS certificates (let's encrypt) and certbot
	  configuration.
  * tls_int
	  renewal of internal TLS certificates (service authorizations) and
	  configuration of authorized internal CA.
	  *(ToDo: deployment of Certificate Revokation Lists)*
  * lxc
      deployment of new containers (deployment of configuration file
	  excluded, for instance change in ip address are always applied and
	  trigger a container restart even if you skip this tag.
  * packages
	  installation and upgrade of software packages (apt, opkg or
	  tarballs)
  * service_password
     create new random password for services-only password, for routine
	 rotation. Not meant to be skipped (some roles need to know the
	 service password, so they do a rotation).

- prepare_host
- ssh_server
- lxc_guest
- ldap
- gitlab

- x509_subject_prefix
- x509_ldap_suffix
	*Replaces:* x509_suffix in ldap.yaml
- letsencrypt_email
	Used in roles/certbot and roles/gitlab
- root_ca_cert
	*Replaces:* ssl_ca_cert and files/lilik_x1.crt

New defaults:

- ldap_domain | default: `${domain}`
- server_fqdn | default: `${hostname}.dmz.${domain}`
	*Replaces:* fqdn_domain

Removed:

- fqdn_dmain
- x509_suffix
	*Replaced by:* x509_ldap_suffix in common

New defaults:

- server_fqdn | default: `${hostname}.${domain}`
   *Replaces*: fqdn
- ldap_domain | default: `${domain}`
- ldap_server | default: `ldap1.dmz.${domain}`
- ldap_basedn | default: `dn(${ldap_domain})`
- enable_https | default: `true`

New defaults:

- server_fqdn | default: `${hostname}.${domain}`

Now xfs is working, `prepare_host.yaml` is modified to add `xfs` to
the list of modules loaded at each boot.

If module is added to that list, than is also loaded with a modprobe
handler.

If xfs is not working with `role/lxc_guest`, run the patched
`prepare_host.yaml` againg.

- New apt multipackage style

- Tabulation in `templates/interfaces.j2` and in `/etc/lvm/lvm.conf`
  line fixed: in Debian buster tabulation is used to indent this config
  files by default.

`python3` and `python3-lxc` are installed with apt instead of `python`
and `python-lxc`.

This commit includes the configuration of vlans on the host
for virtual machines. By configuring a bridge on the br0 interface
we can host the virtual machine vlan and by setting a vlan on the
logical device we can include it into the management vlan.
All variables are included from playbook