VOL-1674 - add version reporting information

Change-Id: Ie6cc244c66077467d371ffb3506ea0f4e817c197
diff --git a/rw_core/config/config.go b/rw_core/config/config.go
index a282b9b..34b5867 100644
--- a/rw_core/config/config.go
+++ b/rw_core/config/config.go
@@ -41,6 +41,7 @@
 	default_KVStoreDataPrefix         = "service/voltha"
 	default_LogLevel                  = 0
 	default_Banner                    = false
+	default_DisplayVersionOnly        = false
 	default_CoreTopic                 = "rwcore"
 	default_RWCoreEndpoint            = "rwcore"
 	default_RWCoreKey                 = "pki/voltha.key"
@@ -74,6 +75,7 @@
 	CoreTopic                 string
 	LogLevel                  int
 	Banner                    bool
+	DisplayVersionOnly        bool
 	RWCoreKey                 string
 	RWCoreCert                string
 	RWCoreCA                  string
@@ -109,6 +111,7 @@
 		CoreTopic:                 default_CoreTopic,
 		LogLevel:                  default_LogLevel,
 		Banner:                    default_Banner,
+		DisplayVersionOnly:        default_DisplayVersionOnly,
 		RWCoreKey:                 default_RWCoreKey,
 		RWCoreCert:                default_RWCoreCert,
 		RWCoreCA:                  default_RWCoreCA,
@@ -193,6 +196,9 @@
 	help = fmt.Sprintf("Show startup banner log lines")
 	flag.BoolVar(&cf.Banner, "banner", default_Banner, help)
 
+	help = fmt.Sprintf("Show version information and exit")
+	flag.BoolVar(&cf.DisplayVersionOnly, "version", default_DisplayVersionOnly, help)
+
 	help = fmt.Sprintf("The name of the meta-key whose value is the rw-core group to which the ofagent is bound")
 	flag.StringVar(&(cf.CoreBindingKey), "core_binding_key", default_CoreBindingKey, help)