Merge branch 'cmake_refactor' into 'master'

CMakeLists.txt

cmake/TestStdFilesystem.cpp

cmake/compileroptions/Clang.cmake

cmake/compileroptions/Cray.cmake

cmake/compileroptions/FujitsuClang.cmake

cmake/compileroptions/GNU.cmake

cmake/compileroptions/IBM.cmake

cmake/compileroptions/Intel.cmake

cmake/compileroptions/IntelLLVM.cmake

cmake/compileroptions/MSVC.cmake

src/core/Filesystem.h

...ially_saturated_cells_method/codegen/PSMWrapperKernels.cu

src/waLBerlaDefinitions.in.h