[CMake] Visual Studio: force use of folders

[Brad King]

On 01/31/2017 05:17 AM, Alexander Hans wrote:
> What we want is to use Visual Studio 2013 as IDE with the vc100 compilers.
> It is possible to create a Visual Studio 2010 solution with CMake and open
> and compile that with Visual Studio 2013.

Instead you should use the "Visual Studio 12 2013" generator but specify
the `vc100` toolset:

  cmake ../src -G "Visual Studio 12 2013" -T vc100

There is also an option in cmake-gui to do this on initial configuration
of a new build tree.  See also these docs:

  https://cmake.org/cmake/help/v3.7/variable/CMAKE_GENERATOR_TOOLSET.html

This way you get native generation for the VS 2013 IDE but the project
will use the `vc100` tools when built.

-Brad