create cmake build configuration

tested only in Linux, likely works in OS X

pkg-config might be too difficult to install in windows for MinGW,
so the best solution is probably to modify CMakeLists.txt, e.g.:

    if(WIN32)
        # ensure glew3 and glfw are installed,
        # set include and library paths
    else()
        find_package(PkgConfig REQUIRED)
        ...
    endif()