When archiving a project, cache for issue/mr counts should be invalidated
When we archive a project, any open issues/merge requests assigned to the user will no longer be counted. The counts in the header will count correctly (once https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/21721 is merged), but the cache will not refresh for up to 20 minutes.
We should consider invalidating the count cache for members of the project that is archived.