Merge remote-tracking branch 'origin/feature/cmake-documentation'

.gitignore

cmake/modules/AddGMPFlags.cmake

cmake/modules/AddMETISFlags.cmake

cmake/modules/AddPTScotchFlags.cmake

cmake/modules/AddParMETISFlags.cmake

cmake/modules/AddUMFPackFlags.cmake

cmake/modules/CMakeBuiltinFunctionsDocumentation.cmake

cmake/modules/CMakeLists.txt

cmake/modules/CheckCXXFeatures.cmake

cmake/modules/DuneCMakePackageConfigHelpers.cmake

cmake/modules/DuneCommonMacros.cmake

cmake/modules/DuneCxaDemangle.cmake

cmake/modules/DuneDoc.cmake

cmake/modules/DuneDoxygen.cmake

cmake/modules/DuneEnableAllPackages.cmake

cmake/modules/DuneMPI.cmake

cmake/modules/DuneMacros.cmake

cmake/modules/DuneSphinxCMakeDoc.cmake

cmake/modules/DuneStreams.cmake

cmake/modules/DuneSymlinkOrCopy.cmake