Updated packages/extra/sdl to be a copy of the posted JEDI-SDL (only specific files).

I will support SDL, SDL_Image, SDL_Mixer, SDL_ttf and SDL_gfx. If anyone wants other SDL parts to be supported they need to provide good testing on all platforms (I use my game ).

I also relicensed those files to LGPL + exception so there are no issues with fpc and or other GPL libs.

Is it all ok Dominique? If something doesn't seem right just contact me