cmake -DDVERSION=6.0.0 to build libdtk6core
install qdbusxml2cpp-fix to DCore/bin to avoid conficts
do not build doc when build dtk6
remove Core5Compat depends
DVERSION ==> DTK_VERSION
tools install to CMAKE_INSTALL_LIBEXECDIR
Now users can simple find_package, and then target_link_libraries with
Dtk::Core. There is no need to invoke target_include_directories,
target_link_libraries will do all things for you.
Log: add cmake target link support
DtkCoreConfig.cmake will always find the library under system library
path. This will cause a linking error when you want to use the version
deployed by yourself. Fix that by appending the path prefix.
Log: fix DtkConfig.cmake.in
Influence: DtkConfig.cmake.in