move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/proto/registry.go

@@ -0,0 +1,10 @@
+package proto
+
+// TypesMap returns mapping from type ids to TL type names.
+func TypesMap() map[uint32]string {
+	return map[uint32]string{
+		MessageContainerTypeID: "message_container",
+		ResultTypeID:           "rpc_result",
+		GZIPTypeID:             "gzip",
+	}
+}