Symfony 3.4/4.0: Support for new PHP-based configuration format

[King2500]

http://symfony.com/blog/new-in-symfony-php-based-configuration-for-services-and-routes

@Haehnchen Can you check what you can do in your plugin to support/auto-complete the new fluent interfaces?

Thanks!

[Haehnchen]

a lot of to do; Lets start with:

• #1041
• #1042

[Wirone]

@Haehnchen any chance for implementing this? There's Symfony 6 now and its team decided to use PHP format internally from this version, I think it will become standard at some point (or maybe it's already happening). Would be great if plugin could support it.