Add some doc. Improve auto documentation of build script
class apache::mod::version(
$apache_version = $::apache::apache_version
) {
if ($::osfamily == 'debian' and versioncmp($apache_version, '2.4') >= 0) {
warning("${module_name}: module version_module is built-in and can't be loaded")
} else {
::apache::mod { 'version': }
}
}