MRG: merge DecisionTree implementation (contribution from J. Inglada)

Code/CMakeLists.txt

Code/Learning/otbDecisionTree.h

Code/Learning/otbDecisionTree.txx

Code/MultiTemporal/CMakeLists.txt

Code/MultiTemporal/foo.cxx

Code/Radiometry/otbVegetationIndicesFunctor.h

Testing/Code/CMakeLists.txt

Testing/Code/Learning/CMakeLists.txt

Testing/Code/Learning/otbDecisionTreeBuild.cxx

Testing/Code/Learning/otbDecisionTreeNew.cxx

Testing/Code/Learning/otbDecisionTreeWithRealValues.cxx

Testing/Code/Learning/otbLearningTests5.cxx

Testing/Code/MultiTemporal/CMakeLists.txt

Testing/Code/MultiTemporal/otbMultiTemporalTests1.cxx

Testing/Code/Radiometry/CMakeLists.txt

.../Code/Radiometry/otbLAIFromNDVILogarithmicFunctorTest.cxx

...de/Radiometry/otbLAIFromReflectancesLinearFunctorTest.cxx

Testing/Code/Radiometry/otbRadiometryTests6.cxx