fix port 80 redirect

1. redirect to whatever host we were called with no matter what api_fqdn
   is set to via using $host.
2. avoid 'taxing' rewrites (http://wiki.nginx.org/Pitfalls#Taxing_Rewrites)
adding dropped @ssl_port back in
Merge pull request #14 from opscode/port-80-redirect

fix port 80 redirect