GaudiConfig2: add DataHandle semantics
Add DataHandle semantics.
In order for the correct property type be reported DataObjectRead/WriteHandle,
the declareProperty call needs to be moved to the derived class.
Closes #308 (closed).
Add DataHandle semantics.
In order for the correct property type be reported DataObjectRead/WriteHandle,
the declareProperty call needs to be moved to the derived class.
Closes #308 (closed).