doc: Add screenshot to spiv page.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
tst_preload: Fix realloc(NULL, size) case.

In case the realloc() was called with NULL optr the code wrongly
searched for the old chunk and caused crash.

The fix is to return malloc(size) in this case instead.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
test: Two fixes for malloc canaries.

* Make use of real_free() instead of free()
  (this fixes posible infinite loop)

* Fix special case for canary_right when size
  is multiple of page size.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
tests: PNG: Add RGBA8888 save test.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
tests: Generate html report by default.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>