Koa2: setting ctx.status prior to ctx.redirect call does not yield any effect.
Is this a bug?

per documentation https://github.com/koajs/koa/blob/v2.x/docs/api/response.md#responseredirecturl-alt

if i set ctx.status prior ctx.redirect call my response status should be set to what ever is i specify it to, but this does not happen in my case. I have middle wear that redirects visitor for any path that does not fall under exception if they do not have authenticated session.

```
        if (authRequired && !ctx.isAuthenticated()) {
            ctx.status = authConfig.authRequiredRedirect.statusCode;
            ctx.redirect(authConfig.authRequiredRedirect.path);
        }
```

![image](https://cloud.githubusercontent.com/assets/658148/20578672/0f30fa84-b18e-11e6-9461-ea3a5ee18d79.png)

Am I missing something?