ENH: put the FORWARD/INVERSE enum for wavelets in its own namespace

Code/MultiScale/otbSubsampleImageFilter.h

Code/MultiScale/otbSubsampleImageFilter.txx

Code/MultiScale/otbWaveletFilterBank.h

Code/MultiScale/otbWaveletFilterBank.txx

Code/MultiScale/otbWaveletHighPassOperator.h

Code/MultiScale/otbWaveletLowPassOperator.h

Code/MultiScale/otbWaveletOperator.h

Code/MultiScale/otbWaveletOperatorBase.h

Code/MultiScale/otbWaveletPacketTransform.h

Code/MultiScale/otbWaveletPacketTransform.txx

Code/MultiScale/otbWaveletTransform.h

Code/MultiScale/otbWaveletTransform.txx

Testing/Code/BasicFilters/CMakeLists.txt

Testing/Code/BasicFilters/otbBasicFiltersTests12.cxx

Testing/Code/MultiScale/CMakeLists.txt

Testing/Code/MultiScale/otbMultiScaleTests4.cxx

Testing/Code/MultiScale/otbSubsampleImageFilter.cxx

Testing/Code/MultiScale/otbSubsampleImageFilterNew.cxx

Testing/Code/MultiScale/otbWaveletFilterBank.cxx

Testing/Code/MultiScale/otbWaveletFilterBankNew.cxx