Sabre-0.2.4 SDL Version

To make this SDL-version of Sabre, obtain the SDL library
(see SDL_PORT_README), and run make in this directory. There should be
an "SDL" directory in the default compiler search path, for example,
/usr/include/SDL, in addition to the SDL lib files.

The scripts flySDL and RunSabreSDL will run this really cool version of
Sabre!


