Temporarily add go-agentx (w/ fixes to lexico ordering)

go-agentx/pdu/packet.go

@@ -0,0 +1,14 @@
+// Copyright 2018 The agentx authors
+// Licensed under the LGPLv3 with static-linking exception.
+// See LICENCE file for details.
+
+package pdu
+
+import "encoding"
+
+// Packet defines a general interface for a pdu packet.
+type Packet interface {
+	TypeOwner
+	encoding.BinaryMarshaler
+	encoding.BinaryUnmarshaler
+}