HTTPS test fixes and improvements:

always skip tests if libcurl do not support HTTPS (instead of failing)
return 99 in case of global errors (MHD-unrelated)
print error result if test if failed
fixed ignored result of epoll test in test_https_get_select
allow compilation by C89 compiler

src/testcurl/https/test_https_time_out.c

@@ -143,5 +143,5 @@ main (int argc, char *const *argv)
   MHD_stop_daemon (d);
   gnutls_global_deinit ();
 
-  return errorCount != 0;
+  return errorCount != 0 ? 1 : 0;
 }