ENH: add a IsValidSensorModel in SensorModelBase and SensorModelWrapper

Code/IO/otbSensorModelWrapper.cxx

Code/IO/otbSensorModelWrapper.h

Code/Projections/otbGenericRSTransform.txx

Code/Projections/otbSensorModelBase.h

Code/Projections/otbSensorModelBase.txx

Examples/Projections/SensorModelExample.cxx

Testing/Code/Projections/otbCompositeTransform.cxx

...g/Code/Projections/otbCreateInverseForwardSensorModel.cxx

Testing/Code/Projections/otbForwardSensorModelGrid.cxx

Testing/Code/Projections/otbRegionProjectionResampler.cxx

Testing/Code/Projections/otbSensorModel.cxx

Testing/Code/Projections/otbSensorModelGrid.cxx