use session varable "fromWhere" for routing whenever it is set

To not route to fromWhere when an email is used to sign up seems unneccesary to me and to do so would be helpful in my szenario.

On a side note: Wouldn't it be nicer to intruduce a new configuration variable like 'signUpSuccessRoute' or so instead of a session variable? There is already a route for the dashboard in config so it would look like a more consistent API. Also I cannot see the advantage of the dynamic a session variable brings to the game.