Add license file and license header in cpp files

CMakeModules/checkAVX2pe.cpp

CMakeModules/checkAVXpe.cpp

CMakeModules/checkSSEpe.cpp

CMakeModules/compileTestAvx.cpp

CMakeModules/compileTestAvx2.cpp

CMakeModules/compileTestIntel.cpp

CMakeModules/compileTestSse.cpp

CMakeModules/getCpuInfos.cpp

CMakeModules/null.cpp

LICENSE

Scripts/LICENSE_HEADER

Scripts/add_license_header.sh

Tests/benchSVD.cpp

UTests/commonParameters.hpp

UTests/testDenseWrappers.cpp

UTests/testGemm.cpp

UTests/testLapackSVD.cpp

UTests/testQRF.cpp

UTests/testRSVD.cpp

UTests/testReadH5.cpp