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/gopkg.in/jcmturner/gokrb5.v7/gssapi/contextFlags.go b/demo_test/vendor/gopkg.in/jcmturner/gokrb5.v7/gssapi/contextFlags.go
new file mode 100644
index 0000000..6634c6d
--- /dev/null
+++ b/demo_test/vendor/gopkg.in/jcmturner/gokrb5.v7/gssapi/contextFlags.go
@@ -0,0 +1,25 @@
+package gssapi
+
+import "github.com/jcmturner/gofork/encoding/asn1"
+
+// GSS-API context flags assigned numbers.
+const (
+	ContextFlagDeleg    = 1
+	ContextFlagMutual   = 2
+	ContextFlagReplay   = 4
+	ContextFlagSequence = 8
+	ContextFlagConf     = 16
+	ContextFlagInteg    = 32
+	ContextFlagAnon     = 64
+)
+
+// ContextFlags flags for GSSAPI
+type ContextFlags asn1.BitString
+
+// NewContextFlags creates a new ContextFlags instance.
+func NewContextFlags() ContextFlags {
+	var c ContextFlags
+	c.BitLength = 32
+	c.Bytes = make([]byte, 4)
+	return c
+}