ISPN-4631 Make sure test servers are shut down before/after tests

https://issues.jboss.org/browse/ISPN-4631
Implementing it as an `@AfterClass` would be definitely better. However, it's done this way as `@AfterClass` method has to be `static`, which means that `protected ContainerController controller` has to be `static` as well and unfortunatelly Arquillian is not able to inject into `static` fields (and AFAIK there's no other way how to initialize `container` properly without using injection)