Documentation - using non-bundled Nginx needs bundled gitlab-git-http-server vhost config

If you are using a non-bundled Nginx, the bundled gitlab-git-http-server does not work and returns an empty repository when cloning.

The example vhost config does not have any configuration for gitlab-git-http-server https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/doc/settings/nginx.md#vhost-server-block

I had to add this in addition to the example vhost config (I got it from the gitlab-ce config and changed the socket path) and now I can clone projects without any issue:

upstream gitlab-git-http-server {
  server unix://var/opt/gitlab/gitlab-git-http-server/socket fail_timeout=0;
}

and inside the server directive

server {
 location ~ [-\/\w\.]+\.git\/ {
    ## If you use HTTPS make sure you disable gzip compression
    ## to be safe against BREACH attack.
    gzip off;

    ## https://github.com/gitlabhq/gitlabhq/issues/694
    ## Some requests take more than 30 seconds.
    proxy_read_timeout      300;
    proxy_connect_timeout   300;
    proxy_redirect          off;

    # Do not buffer Git HTTP responses
    proxy_buffering off;

    # The following settings only work with NGINX 1.7.11 or newer
    #
    # # Pass chunked request bodies to gitlab-git-http-server as-is
    # proxy_request_buffering off;
    # proxy_http_version 1.1;

    proxy_set_header    Host                $http_host;
    proxy_set_header    X-Real-IP           $remote_addr;
    proxy_set_header    X-Forwarded-Ssl     on;
    proxy_set_header    X-Forwarded-For     $proxy_add_x_forwarded_for;
    proxy_set_header    X-Forwarded-Proto   $scheme;
    proxy_pass http://gitlab-git-http-server;
  }
}