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/mtproxy/obfuscator/dialer.go

@@ -0,0 +1,40 @@
+package obfuscator
+
+import (
+	"io"
+	"net"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/mtproxy/obfuscated2"
+)
+
+// Conn is net.Conn wrapper to use Obfuscator.
+type Conn struct {
+	net.Conn
+	Obfuscator
+}
+
+// Obfuscated2 creates new obfuscated2 connection.
+func Obfuscated2(rand io.Reader, conn net.Conn) *Conn {
+	return &Conn{
+		Conn:       conn,
+		Obfuscator: obfuscated2.NewObfuscated2(rand, conn),
+	}
+}
+
+// FakeTLS creates new FakeTLS connection.
+func FakeTLS(rand io.Reader, conn net.Conn) *Conn {
+	return &Conn{
+		Conn:       conn,
+		Obfuscator: newTLS(rand, conn),
+	}
+}
+
+// Write implements io.Writer.
+func (o *Conn) Write(b []byte) (n int, err error) {
+	return o.Obfuscator.Write(b)
+}
+
+// Read implements io.Reader.
+func (o *Conn) Read(b []byte) (n int, err error) {
+	return o.Obfuscator.Read(b)
+}