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/go.mod b/demo_test/vendor/github.com/sirupsen/logrus/go.mod
new file mode 100644
index 0000000..9ea6e84
--- /dev/null
+++ b/demo_test/vendor/github.com/sirupsen/logrus/go.mod
@@ -0,0 +1,11 @@
+module github.com/sirupsen/logrus
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/konsorten/go-windows-terminal-sequences v1.0.1
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/testify v1.2.2
+	golang.org/x/sys v0.0.0-20190422165155-953cdadca894
+)
+
+go 1.13