Added language_code field, see https://core.telegram.org/bots/apiajsdfkadjsfkadjsfkjadsl

chat.go

@@ -29,6 +29,7 @@ type Chat struct {
 	FirstName string `json:"first_name"`
 	LastName  string `json:"last_name"`
 	Username  string `json:"username"`
+	LanguageCode  string `json:"language_code"`
 }
 
 // Recipient returns chat ID (see Recipient interface).