Fixed compilation error on Linux (name conflicts, issue 132)

Load/Save: Fixed display of mount points and drives ("Select drive" button)
Started documenting global variables


git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@698 416bcca6-2ee7-4201-b75f-2eb2f807beb1

sdlscreen.c

@@ -57,7 +57,7 @@ void Set_mode_SDL(int *width, int *height, int fullscreen)
       *width = Screen_SDL->w;
       *height = Screen_SDL->h;
     }
-    Screen=Screen_SDL->pixels;
+    Screen_pixels=Screen_SDL->pixels;
   }
   else
     DEBUG("Error changement de mode video !!",0);