[DI] autowiring-types deprecated in place of aliases

[weaverryan]

See symfony/symfony#21494

Not only do we need to remove autowiring-types, we should show clearly how you can use aliases to choose what class should be autowired for a specific interface/class.

Also, Stof noted that you can/should mark these aliases as private: we don't need them to be available on the final, cached container.

[javiereguiluz]

In case it's useful: https://symfony.com/blog/new-in-symfony-3-3-deprecated-the-autowiring-types

[mvrhov]

With this deprecated, can I get a different path to implement the feature in this PR pomm-project/pomm-bundle@4b99826#diff-f3fa84fa353839f0e811b03d9d0c24b6