SEBA-902 single-olt tests;
Pin protoc-gen-go to 1.3.2 to resolve compatibility issue;
Run go mod tidy / go mod vendor on importer;
Add Go Module support to demotest

Change-Id: Ifde824fc9a6317b0adc1e12bea54ee1f9b788906
diff --git a/demo_test/vendor/github.com/sirupsen/logrus/terminal_check_unix.go b/demo_test/vendor/github.com/sirupsen/logrus/terminal_check_unix.go
new file mode 100644
index 0000000..cc4fe6e
--- /dev/null
+++ b/demo_test/vendor/github.com/sirupsen/logrus/terminal_check_unix.go
@@ -0,0 +1,13 @@
+// +build linux aix
+// +build !js
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+
+func isTerminal(fd int) bool {
+	_, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	return err == nil
+}