minio: Server upon start displays a message if update is available.

This code also handles to turn itself off when network is not
available and if request fails. Also prints only when the update
is available.

globals.go

@@ -16,7 +16,11 @@
 
 package main
 
-import "github.com/fatih/color"
+import (
+	"github.com/fatih/color"
+	"github.com/minio/cli"
+	"github.com/minio/mc/pkg/console"
+)
 
 // Global constants for Minio.
 const (
@@ -33,9 +37,34 @@ const (
 	globalMinioConfigFile    = "config.json"
 )
 
+var (
+	globalQuiet = false // Quiet flag set via command line
+	globalDebug = false // Debug flag set via command line
+	// Add new global flags here.
+)
+
 // global colors.
 var (
 	colorMagenta = color.New(color.FgMagenta, color.Bold).SprintfFunc()
 	colorWhite   = color.New(color.FgWhite, color.Bold).SprintfFunc()
 	colorGreen   = color.New(color.FgGreen, color.Bold).SprintfFunc()
 )
+
+// Set global states. NOTE: It is deliberately kept monolithic to
+// ensure we dont miss out any flags.
+func setGlobals(quiet, debug bool) {
+	globalQuiet = quiet
+	globalDebug = debug
+	// Enable debug messages if requested.
+	if globalDebug == true {
+		console.DebugPrint = true
+	}
+}
+
+// Set global states. NOTE: It is deliberately kept monolithic to
+// ensure we dont miss out any flags.
+func setGlobalsFromContext(ctx *cli.Context) {
+	quiet := ctx.Bool("quiet") || ctx.GlobalBool("quiet")
+	debug := ctx.Bool("debug") || ctx.GlobalBool("debug")
+	setGlobals(quiet, debug)
+}