Add install in CMakeLists.txt

[olivier-fs]

Hi! Nice lib, love DBC concepts à la Eiffel.

I know that I can simply

$ cp pre.h $SOME_CMAKE_INSTALL_PREFIX/include

or add

include_directories($PRECOND_ROOT_DIR)

in the target project CMakeLists.txt.

But it would be so much cleaner to have an install target in precond, so :

• the classic cmake --install --prefix $SOME_CMAKE_INSTALL_PREFIX would work like in many CMake projects (much better for CI/CD toolchain)
• the classic find_package(precond) would find pre.h

Regards

[denniskb]

Hi Olivier, thx for the kind words. Never used cmake's install(), give me a few days to figure it out. Unless you'd like to submit a PR, because I'd gladly accept it :)