Add alias resolution in the has method of the DIC

The `has` method of `Symfony\Component\DependencyInjection` does not resolve services aliases.
This is a bug.

I.E : When enabling the CMF Router, all router's commands of `FrameworkBundle` are disabled because `router` is set as an alias of `cmf_routing.router`. The `has` method doesn't resolve aliases. The `$container->has('router')` call in commands return `false` instead of `true`.