AWS ELB tcp proxy_protocol support

Attempting to enable proxy_protocol support for AWS ELB tcp connections:

https://chrislea.com/2014/03/20/using-proxy-protocol-nginx/

As per:

http://aws.amazon.com/about-aws/whats-new/2013/07/30/elastic-load-balancing-now-supports-proxy-protocol/

Using:

http://www.haproxy.org/download/1.5/doc/proxy-protocol.txt