Rework of No Gravity script: - Now called Gravity, gravity is derived from get away time percentage in game scheme - Watchdog which sets gravity to normal when TurnTimeLeft is frozen for more than 15 seconds

if(WIN32 AND NOT UNIX)
    file(GLOB DLLs *.dll)
    file(GLOB ICOs *.ico)

    install(FILES
        ${DLLs}
        ${ICOs}
        DESTINATION ${target_library_install_dir})
endif(WIN32 AND NOT UNIX)