Add support for Server Alias in Nginx

Adds support for server alias in nginx. Adds a new annotation
which allows us to specify a server alias that will be appended
to the server name.

controllers/nginx/pkg/cmd/controller/nginx.go

@@ -452,6 +452,7 @@ func (n *NGINXController) OnUpdate(ingressCfg ingress.Configuration) error {
 			IP:            svc.Spec.ClusterIP,
 			Port:          port,
 			ProxyProtocol: false,
+
 		})
 	}