Update .gitignore with more demos and tests

Signed-off-by: Matt Turner <mattst88@gmail.com>

.gitignore

@@ -26,25 +26,48 @@ stamp-h?
 config.h
 config.h.in
 .*.swp
+demos/alpha-test
+demos/clip-in
+demos/clip-test
+demos/composite-test
+demos/convolution-test
+demos/gradient-test
+demos/radial-test
+demos/screen-test
+demos/trap-test
+demos/tri-test
 pixman/pixman-combine32.c
 pixman/pixman-combine32.h
 pixman/pixman-combine64.c
 pixman/pixman-combine64.h
 pixman/pixman-version.h
+test/a1-trap-test
+test/affine-test
+test/alpha-loop
+test/alphamap
 test/alpha-test
 test/blitters-test
 test/clip-in
 test/clip-test
 test/composite
 test/composite-test
+test/composite-traps-test
 test/convolution-test
 test/fetch-test
+test/gradient-crash-test
 test/gradient-test
+test/lowlevel-blt-bench
 test/oob-test
+test/pdf-op-test
+test/region-contains-test
 test/region-test
 test/region-translate
+test/region-translate-test
+test/scaling-crash-test
+test/scaling-helpers-test
 test/scaling-test
 test/screen-test
+test/stress-test
 test/trap-crasher
 test/trap-test
 test/window-test