[CMake] Let CMake convert CMAKE_MODULE_PATH to absolute path

[Marcel Loose]

Hi all,

I've been bitten by this more than once. When specifying a module path
on the command line, you must not forget to make this an absolute path,
otherwise calling a macro from a (CMakeLists.txt file in a) subdirectory
will fail.

Would it be an idea to let CMake always convert a relative module path
to an absolute path, before putting it in the cache?

Best regards,
Marcel Loose.