minimal fixes to visual test, so that it actually builds w/o warnings:

- linux_process.c: add an SDLVisualTest_ScreenshotProcess() stub for
  linux builds succeed.
- action_configparser.c: fixes -Wswitch warnings.
- testharness.c: fixes 'is used uninitialized' warnings for userevents.
- testharness.c: fixes format string argument to 'Force killing...'
- testquit.c: fix type of options array in main().
- windows_screenshot.c: lowercase windows.h header name.
- ran dos2unix on all sources and add missing newlines at files' ends.
- minor adjustments to autotools build system (which actually seems to
  need more surgery for unnecessary stuff...)

visualtest/Makefile.in

@@ -1,15 +1,20 @@
 # Makefile to build the SDL tests
+
 srcdir  = @srcdir@
 CC      = @CC@
 EXE	= @EXE@
 CFLAGS  = @CFLAGS@ -I../include -I./include
 LIBS	= @LIBS@
+
 TARGETS = \
 	testharness$(EXE) \
 	testquit$(EXE)
+
 all: Makefile $(TARGETS)
+
 Makefile: $(srcdir)/Makefile.in
 	$(SHELL) config.status $@
+
 testharness$(EXE): $(srcdir)/src/action_configparser.c \
 		   $(srcdir)/src/harness_argparser.c \
 		   $(srcdir)/src/rwhelper.c \
@@ -27,8 +32,10 @@ testharness$(EXE): $(srcdir)/src/action_configparser.c \
 		   $(srcdir)/src/windows/windows_process.c \
 		   $(srcdir)/src/windows/windows_screenshot.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
+
 testquit$(EXE): $(srcdir)/unittest/testquit.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
+
 clean:
 	rm -f $(TARGETS)
 distclean: clean