Update list of cipher suites and add ciphers for TLS 1.3

main.go

@@ -253,11 +253,14 @@ func main() {
 				PreferServerCipherSuites: true,
 				MinVersion:               tls.VersionTLS11,
 
-				// Ciphersuites as defined in stock Go but without 3DES
+				// Ciphersuites as defined in stock Go but without 3DES and RC4
 				// https://golang.org/src/crypto/tls/cipher_suites.go
 				CipherSuites: []uint16{
-					tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
-					tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
+					tls.TLS_AES_128_GCM_SHA256,
+					tls.TLS_AES_256_GCM_SHA384,
+					tls.TLS_CHACHA20_POLY1305_SHA256,
+					tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
+					tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
 					tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
 					tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
 					tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,