Adding a slash at the end of routes, redirects to the wrong address

`https://run.dlang.io/gist/d688bbcfb74c5f9106bf4c1a4f7d19a4` is just fine but `https://run.dlang.io/gist/d688bbcfb74c5f9106bf4c1a4f7d19a4/` redirects to the `8080` port. This seems to be the internal port for the D application.

Also, consider not exposing this port. Passing it to the reverse proxy is desirable to apply proxy rate limits.