Add support for Telegram topics (telegram) (#1942)

Topics are surfaced by appending /<topic-id> to the channel setting for the gateway. 
An example for the topic with ID of 16 would be:

```
[[gateway.inout]]
account="telegram.mytelegram"
channel="-100xxxxxxxxxx/16"
```

1 files changed, 121 insertions, 0 deletions

diff --git a/vendor/github.com/matterbridge/telegram-bot-api/v6/README.md b/vendor/github.com/matterbridge/telegram-bot-api/v6/README.md
new file mode 100644
index 00000000..b18d15dd
--- /dev/null
+++ b/vendor/github.com/matterbridge/telegram-bot-api/v6/README.md
@@ -0,0 +1,121 @@
+# Golang bindings for the Telegram Bot API
+
+[![Go Reference](https://pkg.go.dev/badge/github.com/go-telegram-bot-api/telegram-bot-api/v5.svg)](https://pkg.go.dev/github.com/go-telegram-bot-api/telegram-bot-api/v5)
+[![Test](https://github.com/go-telegram-bot-api/telegram-bot-api/actions/workflows/test.yml/badge.svg)](https://github.com/go-telegram-bot-api/telegram-bot-api/actions/workflows/test.yml)
+
+All methods are fairly self-explanatory, and reading the [godoc](https://pkg.go.dev/github.com/go-telegram-bot-api/telegram-bot-api/v5) page should
+explain everything. If something isn't clear, open an issue or submit
+a pull request.
+
+There are more tutorials and high-level information on the website, [go-telegram-bot-api.dev](https://go-telegram-bot-api.dev).
+
+The scope of this project is just to provide a wrapper around the API
+without any additional features. There are other projects for creating
+something with plugins and command handlers without having to design
+all that yourself.
+
+Join [the development group](https://telegram.me/go_telegram_bot_api) if
+you want to ask questions or discuss development.
+
+## Example
+
+First, ensure the library is installed and up to date by running
+`go get -u github.com/go-telegram-bot-api/telegram-bot-api/v5`.
+
+This is a very simple bot that just displays any gotten updates,
+then replies it to that chat.
+
+```go
+package main
+
+import (
+	"log"
+
+	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
+)
+
+func main() {
+	bot, err := tgbotapi.NewBotAPI("MyAwesomeBotToken")
+	if err != nil {
+		log.Panic(err)
+	}
+
+	bot.Debug = true
+
+	log.Printf("Authorized on account %s", bot.Self.UserName)
+
+	u := tgbotapi.NewUpdate(0)
+	u.Timeout = 60
+
+	updates := bot.GetUpdatesChan(u)
+
+	for update := range updates {
+		if update.Message != nil { // If we got a message
+			log.Printf("[%s] %s", update.Message.From.UserName, update.Message.Text)
+
+			msg := tgbotapi.NewMessage(update.Message.Chat.ID, update.Message.Text)
+			msg.ReplyToMessageID = update.Message.MessageID
+
+			bot.Send(msg)
+		}
+	}
+}
+```
+
+If you need to use webhooks (if you wish to run on Google App Engine),
+you may use a slightly different method.
+
+```go
+package main
+
+import (
+	"log"
+	"net/http"
+
+	"github.com/go-telegram-bot-api/telegram-bot-api/v5"
+)
+
+func main() {
+	bot, err := tgbotapi.NewBotAPI("MyAwesomeBotToken")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	bot.Debug = true
+
+	log.Printf("Authorized on account %s", bot.Self.UserName)
+
+	wh, _ := tgbotapi.NewWebhookWithCert("https://www.example.com:8443/"+bot.Token, "cert.pem")
+
+	_, err = bot.Request(wh)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	info, err := bot.GetWebhookInfo()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if info.LastErrorDate != 0 {
+		log.Printf("Telegram callback failed: %s", info.LastErrorMessage)
+	}
+
+	updates := bot.ListenForWebhook("/" + bot.Token)
+	go http.ListenAndServeTLS("0.0.0.0:8443", "cert.pem", "key.pem", nil)
+
+	for update := range updates {
+		log.Printf("%+v\n", update)
+	}
+}
+```
+
+If you need, you may generate a self-signed certificate, as this requires
+HTTPS / TLS. The above example tells Telegram that this is your
+certificate and that it should be trusted, even though it is not
+properly signed.
+
+    openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 3560 -subj "//O=Org\CN=Test" -nodes
+
+Now that [Let's Encrypt](https://letsencrypt.org) is available,
+you may wish to generate your free TLS certificate there.