The behaviour of the `include` module is badly defined (it try to choose
between statically importing the tasks and dynamically including them)
and can cause problems depending on any number of constraints (mostly if
it choose the wrong behaviour).
Replace it with the `import_tasks` (always statically import tasks) unless
the `include` is in a loop in which case we replace it with
`include_tasks` (always dynamically include tasks).
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.