ENH: DEM handler code review

Modules/Adapters/OSSIMAdapters/test/otbDEMHandlerTest.cxx

...s/Adapters/OSSIMAdapters/test/otbRPCSolverAdapterTest.cxx

...lications/AppProjection/app/otbGenerateRPCSensorModel.cxx

.../Applications/AppProjection/app/otbOrthoRectification.cxx

...s/Applications/AppProjection/app/otbRefineSensorModel.cxx

...ons/AppStereo/app/otbStereoRectificationGridGenerator.cxx

Modules/Core/Transform/include/otbSensorModelAdapter.h

Modules/Core/Transform/src/otbSensorModelAdapter.cxx

Modules/Filtering/DEM/include/otbDEMToImageGenerator.h

Modules/Filtering/DEM/include/otbDEMToImageGenerator.hxx

...iltering/DEM/test/otbDEMToImageGeneratorFromImageTest.cxx

Modules/Filtering/DEM/test/otbDEMToImageGeneratorTest.cxx

...g/Projection/include/otbGCPsToRPCSensorModelImageFilter.h

...Projection/include/otbGCPsToRPCSensorModelImageFilter.hxx

.../test/otbGCPsToRPCSensorModelImageFilterCheckRpcModel.cxx

...ering/Projection/test/otbGenericRSResampleImageFilter.cxx

...tering/Projection/test/otbGenericRSTransformFromImage.cxx

...ring/Projection/test/otbGenericRSTransformGenericTest.cxx

Modules/Filtering/Projection/test/otbSensorModel.cxx

...ing/Projection/test/otbTileImageFilterRSTransformTest.cxx