Netflix/zuul — pull request #98 by kpacha (2014-12-06 16:24:14+00:00)
Title: Request headers to lower case

Force the request headers to be lower case, just like the ones added by Zuul

Why? this way you could overwrite them with `ctx.addZuulRequestHeader("Host", "example.com");` in the PreDecoration filter.

With the current implementation, if you add a custom `Host` header, you could see something like this:

```
REQUEST_DEBUG::ZUUL:: host=http://example.com/
REQUEST_DEBUG::ZUUL::> Host localhost:8080
REQUEST_DEBUG::ZUUL::> Connection keep-alive
REQUEST_DEBUG::ZUUL::> Cache-Control max-age=0
REQUEST_DEBUG::ZUUL::> Accept text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
REQUEST_DEBUG::ZUUL::> User-Agent Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.122 Safari/537.36
REQUEST_DEBUG::ZUUL::> Accept-Language ca,es;q=0.8,en;q=0.6
REQUEST_DEBUG::ZUUL::> host example.com
REQUEST_DEBUG::ZUUL:: > GET /some_url?null HTTP/1.1
```

So let's get fair and treat them equally ;p

```
REQUEST_DEBUG::ZUUL:: host=http://example.com/
REQUEST_DEBUG::ZUUL::> connection keep-alive
REQUEST_DEBUG::ZUUL::> cache-control max-age=0
REQUEST_DEBUG::ZUUL::> accept text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
REQUEST_DEBUG::ZUUL::> user-agent Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.122 Safari/537.36
REQUEST_DEBUG::ZUUL::> accept-language ca,es;q=0.8,en;q=0.6
REQUEST_DEBUG::ZUUL::> host example.com
REQUEST_DEBUG::ZUUL:: > GET /some_url?null HTTP/1.1
```