Patrick, I have written this up based on our discussion. I have also created #4982, but I don't feel that is nearly as important. I'd just like to be able to have rewrites fully work under nginx given official instructions.

For reference, I discussed the importance of Nginx with Patrick, and in summary:
- Nginx is nice, it would be good to not have to rely on having Apache behind it
- Some hosting control panels are pushing Nginx-only now, not Nginx+Apache

Broadly we identified some good reasons for using Nginx:
- Faster for static files
- Allows having multiple sites running off of different ports (for webapps that need to run off of a webroot) but then transparently hosted on arbitrary URLs via reverse proxying
- More modern