defaults: do TLS by default for encryption

Tls has much better throughput, the handshake benchmark is fairly noisy, there is no significant performance difference, however it does allocate more.

```
goos: linux
goarch: amd64
cpu: AMD Ryzen 5 3600 6-Core Processor
BenchmarkNoise/throughput/32KiB-12 24984	     46605 ns/op	 703.10 MB/s	      37 B/op	       2 allocs/op
BenchmarkNoise/throughput/1MiB-12   1134	   1459483 ns/op	 718.46 MB/s	     663 B/op	      34 allocs/op
BenchmarkNoise/handshakes-12        1302	   1054533 ns/op	   32691 B/op	     348 allocs/op
BenchmarkTls/throughput/32KiB-12   49006	     24309 ns/op	1347.99 MB/s	      50 B/op	       2 allocs/op
BenchmarkTls/throughput/1MiB-12     1747	    778498 ns/op	1346.92 MB/s	    1603 B/op	      64 allocs/op
BenchmarkTls/handshakes-12          1116           1045475 ns/op	  105257 B/op	    1478 allocs/op
```

defaults.go

@@ -27,8 +27,8 @@ import (
 // Useful when you want to extend, but not replace, the supported transport
 // security protocols.
 var DefaultSecurity = ChainOptions(
-	Security(noise.ID, noise.New),
 	Security(tls.ID, tls.New),
+	Security(noise.ID, noise.New),
 )
 
 // DefaultMuxers configures libp2p to use the stream connection multiplexers.