Simplify filter download server configuration

modules/filterserver/files/easylist-downloads.adblockplus.org

-# Default
 server {
-  listen       80;
-  listen       [::]:80;
-  listen       443 ssl;
-  listen       [::]:443 ssl;
+  listen 80 default_server;
+  listen [::]:80 default_server;
+  listen 443 ssl default_server;
+  listen [::]:443 ssl default_server;
+
+  server_name easylist-downloads.adblockplus.org easylist-msie.adblockplus.org;
+  access_log /var/log/nginx/access_log_easylist_downloads  main;
+  root /var/www/easylist;
+  keepalive_timeout 0;
+  charset utf-8;
+  gzip_static on;
+  default_type text/plain;
+
   ssl_certificate sites-available/easylist-downloads.adblockplus.org_sslcert.pem;
   ssl_certificate_key sites-available/easylist-downloads.adblockplus.org_sslcert.key;
-  location / {
-    rewrite (.*) $scheme://adblockplus.org$1 permanent;
+
+  set $id "$scheme:$http_host";
+  if ($id = "http:easylist-downloads.adblockplus.org") {
+    rewrite (.*) https://$http_host$1 permanent;
+  }
+
+  error_page 403 404 https://easylist.adblockplus.org/;
+
+  # redirect server error pages to the static page /50x.html
+  #
+  error_page   500 502 503 504  /50x.html;
+  location = /50x.html {
+    root   html;
   }
 }
-# easylist-downloads.adblockplus.org
-server {
-  listen       80;
-  listen       [::]:80;
-  server_name  easylist-downloads.adblockplus.org;
-  location / {
-    rewrite (.*) https://easylist-downloads.adblockplus.org$1 permanent;
-  }
-}
-server {
-  listen       443 ssl;
-  listen       [::]:443 ssl;
-  server_name  easylist-downloads.adblockplus.org;
-  ssl_certificate sites-available/easylist-downloads.adblockplus.org_sslcert.pem;
-  ssl_certificate_key sites-available/easylist-downloads.adblockplus.org_sslcert.key;
-  include "sites-available/inc.easylist-downloads";
-}
-server {
-  listen       80;
-  listen       [::]:80;
-  server_name  easylist-msie.adblockplus.org;
-  include "sites-available/inc.easylist-downloads";
-}