context: add original update to the context

bot.go

@@ -237,7 +237,7 @@ func (b *Bot) NewMarkup() *ReplyMarkup {
 func (b *Bot) NewContext(upd Update) Context {
 	return &nativeContext{
 		b:                b,
-		id:               upd.ID,
+		update:           upd,
 		message:          upd.Message,
 		callback:         upd.Callback,
 		query:            upd.Query,

context.go

@@ -13,12 +13,12 @@ type HandlerFunc func(Context) error
 
 // Context wraps an update and represents the context of current event.
 type Context interface {
-	// ID returns the update ID.
-	ID() int
-
 	// Bot returns the bot instance.
 	Bot() *Bot
 
+	// Update returns the original update.
+	Update() Update
+
 	// Message returns stored message if such presented.
 	Message() *Message
 
@@ -149,7 +149,7 @@ type Context interface {
 type nativeContext struct {
 	b *Bot
 
-	id               int
+	update           Update
 	message          *Message
 	callback         *Callback
 	query            *Query
@@ -165,14 +165,14 @@ type nativeContext struct {
 	store map[string]interface{}
 }
 
-func (c *nativeContext) ID() int {
-	return c.id
-}
-
 func (c *nativeContext) Bot() *Bot {
 	return c.b
 }
 
+func (c *nativeContext) Update() Update {
+	return c.update
+}
+
 func (c *nativeContext) Message() *Message {
 	switch {
 	case c.message != nil: