Re-add section about NGINX config and init script updates in 8.4->8.5 update doc

These sections were removed but:
- even if the NGINX config wasn't
modified, it might be in future updates so it's better to always have it
instead of having to remember to add it depending on the changes
- the init script update section must be there since it's a safe command
  line that should be run on every update

[ci skip]

doc/update/8.4-to-8.5.md

@@ -82,6 +82,32 @@ There are new configuration options available for [`gitlab.yml`](config/gitlab.y
 git diff origin/8-4-stable:config/gitlab.yml.example origin/8-5-stable:config/gitlab.yml.example
 ```
 
+#### Nginx configuration
+
+Ensure you're still up-to-date with the latest NGINX configuration changes:
+
+```sh
+# For HTTPS configurations
+git diff origin/8-4-stable:lib/support/nginx/gitlab-ssl origin/8-5-stable:lib/support/nginx/gitlab-ssl
+
+# For HTTP configurations
+git diff origin/8-4-stable:lib/support/nginx/gitlab origin/8-5-stable:lib/support/nginx/gitlab
+```
+
+If you are using Apache instead of NGINX please see the updated [Apache templates].
+Also note that because Apache does not support upstreams behind Unix sockets you
+will need to let gitlab-workhorse listen on a TCP port. You can do this
+via [/etc/default/gitlab].
+
+[Apache templates]: https://gitlab.com/gitlab-org/gitlab-recipes/tree/master/web-server/apache
+[/etc/default/gitlab]: https://gitlab.com/gitlab-org/gitlab-ce/blob/8-5-stable/lib/support/init.d/gitlab.default.example#L37
+
+#### Init script
+
+Ensure you're still up-to-date with the latest init script changes:
+
+    sudo cp lib/support/init.d/gitlab /etc/init.d/gitlab
+
 ### 8. Start application
 
     sudo service gitlab start