Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe if SDL is built with a non-cdecl calling convention, and it's just generally bad practice anyhow. Now programs explicitly call SDL_Quit() where appropriate, wrap SDL_Quit() in a cdecl function where it can't be avoided, and rely on the parachute where a crash might have hit the atexit() before (these ARE test programs, after all!).

## Makefile.am for SDL using the GEM video driver

noinst_LTLIBRARIES = libvideo_gem.la
libvideo_gem_la_SOURCES = $(GEM_SRCS)

# The SDL GEM video driver sources
GEM_SRCS = 	\
	SDL_gemvideo.h	\
	SDL_gemvideo.c	\
	SDL_gemevents_c.h	\
	SDL_gemevents.c \
	SDL_gemmouse_c.h	\
	SDL_gemmouse.c \
	SDL_gemwm_c.h	\
	SDL_gemwm.c