Add image tag into info output, add ability to print info output on demand and prevent multiple instances of runmqserver being run

cmd/runmqserver/version.go

@@ -29,6 +29,8 @@ var (
 	ImageRevision = "Not specified"
 	// ImageSource is the URL to get source code for building the image
 	ImageSource = "Not specified"
+	// ImageTag is the tag of the image
+	ImageTag = "Not specified"
 )
 
 func logDateStamp() {
@@ -43,6 +45,10 @@ func logGitCommit() {
 	log.Printf("Image source: %v", ImageSource)
 }
 
+func logImageTag() {
+	log.Printf("Image tag: %v", ImageTag)
+}
+
 func logMQVersion() {
 	mqVersion, _, err := command.Run("dspmqver", "-b", "-f", "2")
 	if err != nil {
@@ -67,5 +73,6 @@ func logVersionInfo() {
 	logDateStamp()
 	logGitRepo()
 	logGitCommit()
+	logImageTag()
 	logMQVersion()
 }