BASE: correct to official description
ALL: unify setupScreen() arguments type
SDL: add support for SDL2
SDL2: added support for mdvc
SDL2: revert makefile enable SDL2 to original. added instead disabling SDL audio in source code to be compatible with MSVC
SDL2: changed way how to deal with forbidden symbols
SDL2: added comment to SDL win32
SDL2: use dynamic cast
SDL2: make OpenGL forward compatible
SDL2: changed error messages, SDL return his own.
SDL2: disabled GL forward compatible mode, it seems fail create context on 3.0 GL driver, probably because not setting version of context
SDL2: added/updated few comments