adds vendor directory

vendors dependencies in standard `vendor` directory, managed by glide

vendor/github.com/mattn/go-gtk/example/statusicon/statusicon.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"fmt"
+	"github.com/mattn/go-gtk/glib"
+	"github.com/mattn/go-gtk/gtk"
+	"os"
+)
+
+func main() {
+	gtk.Init(&os.Args)
+
+	glib.SetApplicationName("go-gtk-statusicon-example")
+
+	mi := gtk.NewMenuItemWithLabel("Popup!")
+	mi.Connect("activate", func() {
+		gtk.MainQuit()
+	})
+	nm := gtk.NewMenu()
+	nm.Append(mi)
+	nm.ShowAll()
+
+	si := gtk.NewStatusIconFromStock(gtk.STOCK_FILE)
+	si.SetTitle("StatusIcon Example")
+	si.SetTooltipMarkup("StatusIcon Example")
+	si.Connect("popup-menu", func(cbx *glib.CallbackContext) {
+		nm.Popup(nil, nil, gtk.StatusIconPositionMenu, si, uint(cbx.Args(0)), uint32(cbx.Args(1)))
+	})
+
+	fmt.Println(`
+Can you see statusicon in systray?
+If you don't see it and if you use 'unity', try following.
+
+# gsettings set com.canonical.Unity.Panel systray-whitelist \
+  "$(gsettings get com.canonical.Unity.Panel systray-whitelist \|
+  sed -e "s/]$/, 'go-gtk-statusicon-example']/")"
+`)
+
+	gtk.Main()
+}