MVC 6 rewrite errors instead of redirect

[jhermsen]

Hi I have a little issue.
I though the error pages would rewrite instead of redirect, but when I get a 404 error I get redirected to /error/404.
I think google search craweler might have an issue with this as it is seeying a page as permanently moved instead of not available.

[RehanSaeed]

Merging your fix.