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/.travis.yml b/demo_test/vendor/github.com/sirupsen/logrus/.travis.yml
new file mode 100644
index 0000000..5e20aa4
--- /dev/null
+++ b/demo_test/vendor/github.com/sirupsen/logrus/.travis.yml
@@ -0,0 +1,17 @@
+language: go
+go_import_path: github.com/sirupsen/logrus
+git:
+  depth: 1
+env:
+  - GO111MODULE=on
+go: [1.13.x, 1.14.x]
+os: [linux, osx]
+install:
+  - ./travis/install.sh
+script:
+  - ./travis/cross_build.sh
+  - ./travis/lint.sh
+  - export GOMAXPROCS=4
+  - export GORACE=halt_on_error=1
+  - go test -race -v ./...
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then go test -race -v -tags appengine ./... ; fi