GuzzleHttp requests examples

[adrianharabula]

The sync version

        $client = new \GuzzleHttp\Client();
        $request =  $client->get('https://webhooks.condr.me/version');
        $message = $request->getBody();

The Async version

        $client = new \GuzzleHttp\Client();
        $promise =  $client->getAsync('https://webhooks.condr.me/version');

        $promise->then(
            function (ResponseInterface $res) {
                $msg = (string) $res->getBody();
                \Debugbar::notice(msg);
            },
            function (RequestException $e) {
                echo $e->getMessage() . "\n";
                echo $e->getRequest()->getMethod();
            }
        );

[adrianharabula]

maybe add this to documentation