content: add 7years.article

Change-Id: Ifa117d9d8c6514f598a944f02d11f60c6afc6bc5
Reviewed-on: https://go-review.googlesource.com/33021
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
4 files changed