Don't overwrite options in setup.cmake.
Align text in summary message.
Always set wxUSE_XRC to values of wxUSE_XRC, same as in setup.h.
Disable wxUSE_XRC when expat is disabled.
Add CMake build system for libraries, tests and samples
update_files.py converts build/files into CMake format.
build/update-setup-h has been modified to update build/cmake/setup.h.in.