Separate linux/win libs to lib/{win,linux}

Separate linux/win libs to lib/{win,linux}
Avoids conflicts when windows and linux compile at the same time

    devtools.sh
    external/flite/lang/SConscript
    external/flite/main/SConscript
    external/flite/src/SConscript
    external/noise/src/SConscript
    external/polyvox/library/PolyVoxCore/SConscript
    external/polyvox/library/PolyVoxUtil/SConscript
    src/SConscript
    utils/linux_build.py
    utils/win_build.py
Fixed FileUtil::Rename for windows

Fixed FileUtil::Rename for windows
Made rename behavior same for windows/linux, as std::rename
doesn't override in windows.
    src/util/FileUtil.cpp
    src/util/TestFile.h
    src/util/TestFileUtil.h