Remove redirects and update error page
We briefly discussed this at the metrics team meeting yesterday. There are still some quite old redirects in place on Tor Metrics. We concluded that we should turn them into "manual redirects" where we only display the link rather than redirecting users automatically, forcing them to notice and update their bookmarks accordingly. However, I read today that using 301 status codes is just fine for redirecting.
Now I wonder if the manual redirect idea might be a step backwards, because then there will be "content" again for search engines to index, which seems wrong. Maybe we can simply remove these redirects after 9 months. Users should notice that the URL has changed, shouldn't they?
While looking at the code I also found that our error page contains an outdated sitemap with many links that would need to be redirected. We should simply remove those links.
I'll attach a branch in a minute once I have a ticket number.