Use configuration to add container parameters

Otherwise the following definition
``` yaml
app:
    foo: bar

services:
    app.foo_manager
        arguments:
            - "%app.foo%"
```

will throw

 ```
  [Symfony\Component\DependencyInjection\Exception\ParameterNotFoundException]
  The service "app.foo_manager" has a dependency on a non-existent parameter "app.foo".
```