provide args for telegraf for consistency with influxd:

- telegraf version
- telegraf config

closes #857

cmd/telegraf/telegraf.go

@@ -96,8 +96,9 @@ func main() {
 		reload <- false
 		flag.Usage = func() { usageExit(0) }
 		flag.Parse()
+		args := flag.Args()
 
-		if flag.NFlag() == 0 {
+		if flag.NFlag() == 0 && len(args) == 0 {
 			usageExit(0)
 		}
 
@@ -121,6 +122,18 @@ func main() {
 			outputFilters = strings.Split(":"+outputFilter+":", ":")
 		}
 
+		if len(args) > 0 {
+			switch args[0] {
+			case "version":
+				v := fmt.Sprintf("Telegraf - Version %s", Version)
+				fmt.Println(v)
+				return
+			case "config":
+				config.PrintSampleConfig(inputFilters, outputFilters)
+				return
+			}
+		}
+
 		if *fOutputList {
 			fmt.Println("Available Output Plugins:")
 			for k, _ := range outputs.Outputs {