TEST: add first tests for DR models (WIP)

...rning/DimensionalityReductionLearning/test/CMakeLists.txt

...onalityReductionLearning/test/otbAutoencoderModelTest.cxx

...ing/test/otbDimensionalityReductionLearningTestDriver.cxx

...arning/test/otbImageDimensionalityReductionFilterTest.cxx

.../DimensionalityReductionLearning/test/otbPCAModelTest.cxx

.../DimensionalityReductionLearning/test/otbSOMModelTest.cxx