[VC] Fix codes for Win32 platform.
- Add CCApplicationProtocol::applicationWillTerminate()
- Call applicationWillTerminate() in CCDirector::purgeDirector()
- In CCApplication::run(), sleep 1 ms instead of 0 ms.
- Check CCDirector::getOpenGLView() before applicationWillEnterForeground()
- Call applicationDidEnterBackground() in WM_CLOSE.
- Don't remove MIN/MAX macros.
- Use _WIN32 to detect Win32 platform.
[VC] Add libCocosDenshion reference to libCocos2d project.
- Remove linker dependences libcocod2d.lib