Change the minimum version to 3.0. Version 2.8.12 has never worked,
because it does not support the VERSION parameter in project().
Replace GREATER_EQUAL comparisons, these are only supported since 3.7.
Move PCH related code to a separate file, and include it after
options.cmake and init.cmake. Because only then the wxBUILD_PRECOMP
variable is fully initialized.
Closes#22312.
Put each benchmark application in a sub-directory instead of specifying all in one
file, because cotire cannot create PCH targets for the same file twice (bench.cpp).
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-based build system.
Merge the original branch without any changes except for resolving the
conflict due to moving the contents of .travis.yml to a separate file by
propagating the changes done in this file since then to the new script
and rerunning ./build/update-setup-h and ./build/cmake/update_files.py
to update the file lists changed in the meanwhile.
Closes https://github.com/wxWidgets/wxWidgets/pull/330
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.
