session-cookie doesn't work with redirect
It is not possible to update a cookie in a redirect, therefore if npm `cookie-session` module is used and redirect, the data is never set here:
https://github.com/simov/grant/blob/master/lib/handler/express-4.js#L45

Here is the debugger showing the data exist and it does a redirect, but the http header `set-cookie` is never done:

![image](https://user-images.githubusercontent.com/1126497/82758481-16939b80-9de7-11ea-9068-409d5707798b.png)

Here is a issue that also confirms it: https://github.com/expressjs/cookie-session/issues/70#issuecomment-265501578

I don't think this example with cookie-session works: https://github.com/simov/grant/blob/master/examples/handler-express/cookie-session.js#L8