created QS SDL2 target
SDL2 target: link SDL2.framework from /Library/Frameworks, include in app
SDL2 target: remove double quotes around LIBRARY_SEARCH_PATHS values, this breaks linking on my OS X 10.6/Xcode 3.2.6 system. Drop ppc from SDL2 target. Add USE_SDL2 define
Fix Info.plist reference
Bump minimum sdk deployment target to 10.5 for x86 to fix sdl2 build