VS2005 tweaks (thanks, Ozkan!). Fixes Bugzilla #2895. His notes: The following trivial changes make SDL2 tree (mostly) compatible with Visual Studio 2005: * SDL_stdlib.c: Similar to VS2010 and newer, VS2005 also generates memcpy(), (it also generates memset(), see below), so propagate the #if condition to cover VS2005. * SDL_pixels.c (SDL_CalculateGammaRamp): VS2005 generates a memset() call for gamma==0 case, so replace the if loop with SDL_memset(). * SDL_windowsvideo.h: Include msctf.h only with VS2008 and newer, otherwise include SDL_msctf.h * SDL_windowskeyboard.c: Adjust the #ifdefs so that SDL_msctf.h inclusion is always recognized correctly.