tests: log the test result code after each libtest

This makes it easier to determine the test status. Also, capitalize
FAILURE and ABORT messages in log lines to make them easier to spot.

tests/libtest/first.c

@@ -172,6 +172,7 @@ int main(int argc, char **argv)
   fprintf(stderr, "URL: %s\n", URL);
 
   result = test(URL);
+  fprintf(stderr, "Test ended with result %d\n", result);
 
 #ifdef WIN32
   /* flush buffers of all streams regardless of mode */