use nginx 1.9.1 and reuseport to get socket sharding

bin/compile

@@ -9,7 +9,7 @@ env_dir=$3
 bp_dir=$(dirname $(dirname $0))
 
 fetch_nginx_tarball() {
-    local version="1.8.0"
+    local version="1.9.1"
     local tarball_file="nginx-$version.tgz"
     local stack="cedar-14"
     local nginx_tarball_url="https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/nginx/$stack/nginx-$version.tgz"

scripts/config/templates/nginx.conf.erb

@@ -28,7 +28,7 @@ http {
   client_body_timeout 5;
 
   server {
-    listen <%= port %>;
+    listen <%= port %> reuseport;
     keepalive_timeout 5;
     root <%= root %>;
   <% if error_page %>