message: Made the adjoint operators test double when compiling without cuda
diff: int main(int, char** )
  {
  const unsigned int Dimension = 3;
  - typedef float OutputPixelType;
  #ifdef USE_CUDA
  + typedef float OutputPixelType;
  typedef itk::CudaImage< OutputPixelType, Dimension > OutputImageType;
  #else
  + typedef double OutputPixelType;
  typedef itk::Image< OutputPixelType, Dimension > OutputImageType;
  #endif
  @@ -155,6 +156,7 @@ int main(int, char** )
  bp->SetInput(0, constantVolumeSource->GetOutput());
  bp->SetInput(1, randomProjectionsSource->GetOutput());
  bp->SetGeometry( geometry.GetPointer() );
  + bp->SetNumberOfThreads(1);
  TRY_AND_EXIT_ON_ITK_EXCEPTION( bp->Update() );
  