[NET] Refactor TLS configuration.

Use a TLSOptions configuration object which is created via static
functions.

- "TLSOptions.client": uses the standard CA and common name verification.
- "TLSOptions.client_unsafe": uses optional CA verification (i.e. if specified)
- "TLSOptions.server": is the standard server configuration (chain + key)

This will allow us to expand the TLS configuration options to include
e.g. mutual authentication without bloating the classes that uses
StreamPeerTLS and PacketPeerDTLS as underlying peers.

platform/web/export/editor_http_server.h

@@ -206,7 +206,7 @@ public:
 				tls = Ref<StreamPeerTLS>(StreamPeerTLS::create());
 				peer = tls;
 				tls->set_blocking_handshake_enabled(false);
-				if (tls->accept_stream(tcp, key, cert) != OK) {
+				if (tls->accept_stream(tcp, TLSOptions::server(key, cert)) != OK) {
 					_clear_client();
 					return;
 				}