Correct reinitialization of Global singleton object and support LifecycleManaer.destroy

Before this patch, reinitialization was broken since the injector was cached. This meant that in a second application start the old service instances were reused.

That is problematic in tests if bound instances are stateful. E.g. an ActorSystem which is shut down on application stop.

The problem is demonstrated in the supplied ScaldiSupportTest.