I have no idea how this got past testing, but apparently, the task
did not even exist..

We used to prefer creating a specific one for backups, but everybody
kept thinking the wrong key was being used and "fixing" it. The
advantages of having a specific key for backups did not outweigh
the challenge of creating a culture change.

This allows us to remove the shellcheck ignore warning comment and puts it in line with upstream. Apparently, the file can only contain one PID, so it's okay to quote the variable.

This makes sure that nothing inside the script is parsed by jinja
unless we want it.

The default file should be used for configuration instead of the init 
script.

Closes #98

Signed-off-by: Ludovic Poujol <lpoujol@evolix.fr>

Introducing a new variable `packweb_multiphp_versions: []`.
While set empty, packweb-apache will setup a regular packweb.
When filled with PHP Versions, it will handle :
- LXC Container setup and config (as a dependencie of lxc-php role)
- Ensure evoadmin-web will set the rights versions in the config files
  by setting evoadmin_multiphp_versions

Exemple value :  `packweb_multiphp_versions: ['php70', 'php73']`
That will call lxc-php to create both PHP 7.0 and PHP 7.3 containers.

Instead of having evoadmin_multi_php as a boolean, and outputing all 
versions possible PHP version in evoadmin, we now have 
evoadmin_multiphp_versions.

It's supposed to be a

This is a breaking change as lxc-php should now be called for *each* php 
containers we want, with the correct lxc_php_version variable.

Current valid values are : 
- php56
- php70
- php73

Other changes includes : 
- LXC Containers are created by calling lxc as a dependency of the role.
- Relying on lxc_container module to do commands into the container 
(instead of the command module)
- PHP 7.3 container is now a Debian Buster container
- All containers will have opensmtpd to relay emails to postfix on the 
host system.