Issue #69: pulled 'dense_vnet' case over from run_application.py to niftynet/__init__.py
Issue #69: pulled 'dense_vnet' case over from run_application.py to niftynet/__init__.py

NifTK/NiftyNet,NifTK/NiftyNet,NifTK/NiftyNet,NifTK/NiftyNet