Refactored Thing to return bridge UID instead of bridge object. …
Enhanced StorageService interface to take ClassLoader as second argument.
Using getService with ClassLoader in ManagedItemChannelLinkProvider, ManagedItemProvider and ManagedThingProvider.
Added transient modifier to fields in domain classes, that must not be persisted.
Moved VolatileStorage to test bundle and adapted tests.
Removed StorageSelector and refactored managed provider to use one service only.

Signed-off-by: Dennis Nobel <d.nobel@external.telekom.de>