anchor.diff:        ..usePrivateKey('dev.key', password: 'dartdart')
         ..setAlpnProtocols(['h2'], true);
   
  -    http2 = AngelHttp2(app, ctx);
  +    http2 = AngelHttp2(app, ctx, allowHttp1: true);
   
       var server = await http2.startServer();
       serverRoot = Uri.parse('https://127.0.0.1:${server.port}');
  
positive.code: 
  void main() {
    var client = Http2Client();
    Angel app;
    AngelHttp2 http2;
    Uri serverRoot;
  
negative.code: 
    tearDown(() async {
      await http2.close();
      await h1c.close();
    });
  
    test('buffered response', () async {
      var response = await client.get(serverRoot);
      expect(response.body, 'Hello world');
    });
  
    test('allowHttp1', () async {
      var response = await h1c.get(serverRoot);
      expect(response.body, 'Hello world');
    });
  
  