adds vendor directory

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

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

@@ -0,0 +1,55 @@
+package main
+
+import (
+	"fmt"
+	"github.com/mattn/go-gtk/gdk"
+	"github.com/mattn/go-gtk/glib"
+	"github.com/mattn/go-gtk/gtk"
+	"unsafe"
+)
+
+func main() {
+	gtk.Init(nil)
+
+	window := gtk.NewWindow(gtk.WINDOW_TOPLEVEL)
+	window.SetPosition(gtk.WIN_POS_CENTER)
+	window.SetTitle("GTK Go!")
+	window.SetIconName("textview")
+	window.Connect("destroy", gtk.MainQuit)
+
+	textview := gtk.NewTextView()
+	textview.SetEditable(true)
+	textview.SetCursorVisible(true)
+	var iter gtk.TextIter
+	buffer := textview.GetBuffer()
+
+	buffer.GetStartIter(&iter)
+	buffer.Insert(&iter, "Hello ")
+
+	tag := buffer.CreateTag("bold", map[string]string{"background": "#FF0000", "weight": "700"})
+	buffer.InsertWithTag(&iter, "Google!", tag)
+
+	u := "http://www.google.com"
+	tag.SetData("tag-name", unsafe.Pointer(&u))
+	textview.Connect("event-after", func(ctx *glib.CallbackContext) {
+		arg := ctx.Args(0)
+		if ev := *(**gdk.EventAny)(unsafe.Pointer(&arg)); ev.Type != gdk.BUTTON_RELEASE {
+			return
+		}
+		ev := *(**gdk.EventButton)(unsafe.Pointer(&arg))
+		var iter gtk.TextIter
+		textview.GetIterAtLocation(&iter, int(ev.X), int(ev.Y))
+		tags := iter.GetTags()
+		for n := uint(0); n < tags.Length(); n++ {
+			vv := tags.NthData(n)
+			tag := gtk.NewTextTagFromPointer(vv)
+			u := *(*string)(tag.GetData("tag-name"))
+			fmt.Println(u)
+		}
+	})
+
+	window.Add(textview)
+	window.SetSizeRequest(600, 600)
+	window.ShowAll()
+	gtk.Main()
+}