Commandline DEMO; resampleFilter uses itkImageDomainFixed

comply with pipeline functionality

RegistrationMethod.

itkImageRegistrationMethod

with Bug ElastixFilter->GetParameterObject() solved.

ENH: WBIRDemoTest
ENH: transformix writes deformation field
ENH: itkv4 registration runs 3 levels (hard coded)
ENH: itkv4 exposes forward deformationfield (still with some workarounds)
ENH: itkv4 exposes transformed moving image (still with some workarounds)
BUG: itkv4 MeanSquares Component initiated wrong Metric

directly an itkImage.
This is useful for bypassing the itkpipeline mechanism. (As for
elastixfilter currently). If the itkpipeline is bypassed, the (update)
control flow must be handed over to the Overlord. This is done via the
AfterRegistration mechanism in Overlord.

ENH: reorganized Sink and Souce file structure

added RunRegistrationInterface

ComponentSelector

The ItkSmoothingRecursiveGaussianImageFilterComponent is templated over
the dimensionality and pixeltype of in- and output. Stings "Dimensionality" and
"PixelType" are added as Criteria to select the right Component.