DefaultCacheManager inconsistent status checks

DefaultCacheManager.getTransport() returns null when the manager is stopping, it should not.

To make things worse, DefaultCacheManager.getStatus() returns the status of the GlobalComponentRegistry, which is still RUNNING while caches are shutting down. That means DCM.getTransport() and DCM.getAddress() return null while the cache are stopping, and breaks distributed streams on caches that are still running.