Merge pull request #479 from edx/cg/nginx_ssl_log_format

Added additional log format for use with client SSL certificates

playbooks/roles/nginx/templates/nginx.conf.j2

@@ -36,6 +36,11 @@ http {
         log_format p_combined '$http_x_forwarded_for - $remote_addr - $remote_user [$time_local]  '
                             '"$request" $status $body_bytes_sent $request_time '
                             '"$http_referer" "$http_user_agent"';
+
+        log_format ssl_combined '$remote_addr - $ssl_client_s_dn [$time_local]  '
+                                '"$request" $status $body_bytes_sent '
+                                '"$http_referer" "$http_user_agent"';
+
         access_log {{ nginx_log_dir }}/access.log p_combined;
         error_log {{ nginx_log_dir }}/error.log;