_content/doc/gopher: redirect to blog post
_content/doc/gopher: redirect to blog post

Redirecting to the blog post telling the story of the gopher
is nicer than showing a bare directory listing.

Change-Id: I8b18faed5e4a9cee95d803b4d1c00fd5d5eb5834
Reviewed-on: https://go-review.googlesource.com/c/website/+/362503
Trust: Russ Cox <5ad239cb8a44f659eaaee0aa1ea5b94947abe557@golang.org>
Reviewed-by: Jamal Carvalho <e0195770807aa8c82b0b128d9c0423b5ad035172@golang.org>

golang/website,golang/website,golang/website,golang/website,golang/website,golang/website,golang/website