Refs #12832 Add normalization to some MDAlgorithims

Code/Mantid/Framework/API/inc/MantidAPI/IMDHistoWorkspace.h

...work/DataObjects/inc/MantidDataObjects/MDHistoWorkspace.h

Code/Mantid/Framework/DataObjects/src/MDHistoWorkspace.cpp

Code/Mantid/Framework/MDAlgorithms/src/BinMD.cpp

.../Framework/MDAlgorithms/src/IntegrateMDHistoWorkspace.cpp

Code/Mantid/Framework/MDAlgorithms/src/MDNormDirectSC.cpp

Code/Mantid/Framework/MDAlgorithms/src/SliceMD.cpp

Code/Mantid/Framework/MDAlgorithms/test/BinMDTest.h

Code/Mantid/Framework/MDAlgorithms/test/CutMDTest.h

...amework/MDAlgorithms/test/IntegrateMDHistoWorkspaceTest.h

Code/Mantid/Framework/MDAlgorithms/test/MDNormDirectSCTest.h

Code/Mantid/Framework/MDAlgorithms/test/SliceMDTest.h