TUN-4597: Add a QUIC server skeleton

- Added a QUIC server to accept streams
- Unit test for this server also tests ALPN
- Temporary echo capability for HTTP ConnectionType

vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_noasm.go

@@ -0,0 +1,15 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !amd64 gccgo purego
+
+package chacha20poly1305
+
+func (c *chacha20poly1305) seal(dst, nonce, plaintext, additionalData []byte) []byte {
+	return c.sealGeneric(dst, nonce, plaintext, additionalData)
+}
+
+func (c *chacha20poly1305) open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
+	return c.openGeneric(dst, nonce, ciphertext, additionalData)
+}