the wrapper sounds good, since this way we expose everything without just adding a lot of methods to the HttpRequest. 
Should I deprecate 
```java
public String header(String name) {
```
and change the places where this is used(only 2 places) to access the value through the wrapper class?

Also, looking at the way the code is organized, it feels I should create

interface ```org.elasticsearch.rest.RestHeaders``` 
interface ```org.elasticsearch.http.HttpHeaders``` extends RestHeaders
class ```org.elasticsearch.http.netty.NettyHttpHeaders``` implements HttpHeaders

even though it might not make a lot of sense on doing so. Just let me know and I will update the PR.