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/go.mod b/go.mod
index 218ddb6..824a3c7 100644
--- a/go.mod
+++ b/go.mod
@@ -5,11 +5,10 @@
 require (
 	github.com/Shopify/sarama v1.26.1
 	github.com/golang/protobuf v1.3.5
-	github.com/grpc-ecosystem/grpc-gateway v1.14.3 // indirect
 	github.com/jessevdk/go-flags v1.4.0
 	github.com/sirupsen/logrus v1.5.0
-	github.com/stretchr/objx v0.1.1 // indirect
 	golang.org/x/net v0.0.0-20200202094626-16171245cfb2
+	google.golang.org/genproto v0.0.0-20190927181202-20e1ac93f88c // indirect
 	google.golang.org/grpc v1.28.1
 	gopkg.in/yaml.v2 v2.2.8
 )