add FTOS test file
diff --git a/extensions/.FTOS-test b/extensions/.FTOS-test
new file mode 100755
index 0000000..d07fce7
--- /dev/null
+++ b/extensions/.FTOS-test
@@ -0,0 +1,2 @@
+#! /bin/sh
+[ -f $KERNEL_DIR/include/linux/netfilter_ipv4/ipt_FTOS.h ] && echo FTOS