[RFR] Allow the bundle to launch phpunit tests as standalone

The tests can be launched now: may notice one of them is broken, because the related RouterLoader service is not complete for now /c @arkaitzgarro 

I've removed ``composer.lock`` file too, I don't know when this file has been introduced but it's a bad practice to keep it.

So, it's ready for review :)
How about using >=?

We should change all these dependencies from `>=` to `~`.