Fixed custom ParameterResolverFactory support in annotated aggregates

The ParameterResolverFactory can now be attached to the Unit of Work. When an
aggregate is created outside the scope of an AggregateFactory, the aggregate
tries to pick up the PRF from the UoW. If not present, it will resort to the
default implementation.

Issue #AXON-265 Fixed
Fix for Axon-263: Saga managers don't accept multiple base packages for scanning. The base-package value is now split on comma before processing.
Adapted unit tests for multi-package support in saga manager

Issue #AXON-263 Fixed
Fixed issue where classpath scanning for Saga reveils no instances

The SagaManager would throw an exception when initialized without any concrete
instances.

Issue #AXON-264 Fixed
AuditLogger interface issue

The interface declares an Object as type of message. However, at runtime the
command is always an instance of CommandMessage. The interface has been
modified.

Issue #AXON-251 Fixed