nginx: Log to syslog by default

Suppress nginx's stdout/stderr because it's not possible to stop nginx
from logging to stderr once it has been enabled, and it's enabled by
default (via compilation option).

Move the error_log to the root context as it applies to more than http.

The logrotate setup installed by nginx doesn't actually rotate the text
log files we've been using.

planet and sources roles still install configs that use text log files.

roles/nginx/files/nginx.service.d

+[Service]
+StandardOutput=null

roles/nginx/tasks/main.yml

@@ -3,6 +3,9 @@
 - name: install nginx
   pacman: name=nginx,certbot state=present
 
+- name: install nginx.service snippet
+  copy: src=nginx.service.d dest=/etc/systemd/system/nginx.service.d/local.conf owner=root group=root mode=0644
+
 - name: configure nginx
   template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf owner=root group=root mode=0644
   notify:

roles/nginx/templates/nginx.conf.j2

@@ -4,6 +4,8 @@ events {
     worker_connections  1024;
 }
 
+error_log syslog:server=unix:/dev/log,nohostname info;
+
 http {
     include       mime.types;
     default_type  application/octet-stream;
@@ -14,8 +16,7 @@ http {
 
     index  index.php index.html index.htm;
 
-    access_log   /var/log/nginx/default/access.log;
-    error_log    /var/log/nginx/default/error.log;
+    access_log syslog:server=unix:/dev/log,nohostname,tag=nginx_http;
 
     include snippets/sslsettings.conf;