feat: provide short version [#1179]

cmd/cloudflared/main.go

@@ -134,11 +134,22 @@ To determine if an update happened in a script, check for error code 11.`,
 		{
 			Name: "version",
 			Action: func(c *cli.Context) (err error) {
+				if c.Bool("short") {
+                    fmt.Println(strings.Split(c.App.Version, " ")[0])
+                    return nil
+                }
 				version(c)
 				return nil
 			},
 			Usage:       versionText,
 			Description: versionText,
+			Flags: []cli.Flag{
+                &cli.BoolFlag{
+                    Name:    "short",
+                    Aliases: []string{"s"},
+                    Usage:   "print just the version number",
+                },
+            },
 		},
 	}
 	cmds = append(cmds, tunnel.Commands()...)