Merge #1615 선택적 세션 시작 (Proof of Concept) by kijin

* pr/1615:
  Force start session if SSO is used
  Improve and simplify session status detection
  Improve handling of session variables related to validator
  Start session automatically if an addon uses the session and exits
  If cache-friendly behavior is enabled, don't skip updateReadedCount()
  If cache-friendly behavior is enabled, don't update session when reading document or comment
  Add option to enable/disable cache-friendly behavior
  Improve the setCacheControl() method
  Context::setCacheControl() method added etc.
  do not always set mobile/user-agent cookies
  선택적 세션 시작 + 서드파티 자료 호환성 (Proof of Concept)

modules/admin/admin.admin.view.php

@@ -71,6 +71,7 @@ class adminAdminView extends admin
 		Context::set('use_html5', $db_info->use_html5 == 'Y' ? 'Y' : 'N');
 		Context::set('use_spaceremover', $db_info->use_spaceremover ? $db_info->use_spaceremover : 'Y'); //not use
 		Context::set('qmail_compatibility', $db_info->qmail_compatibility == 'Y' ? 'Y' : 'N');
+		Context::set('cache_friendly', $db_info->cache_friendly == 'Y' ? 'Y' : 'N');
 		Context::set('use_db_session', $db_info->use_db_session == 'N' ? 'N' : 'Y');
 		Context::set('use_mobile_view', $db_info->use_mobile_view == 'Y' ? 'Y' : 'N');
 		Context::set('use_ssl', $db_info->use_ssl ? $db_info->use_ssl : "none");

modules/admin/lang/lang.xml

@@ -760,6 +760,18 @@
 		<value xml:lang="zh-CN"><![CDATA[启用Qmail]]></value>
 		<value xml:lang="tr"><![CDATA[Qmail etkinleştirin]]></value>
 	</item>
+	<item name="cache_friendly">
+		<value xml:lang="ko"><![CDATA[캐싱 최적화]]></value>
+		<value xml:lang="en"><![CDATA[Optimize for caching]]></value>
+		<value xml:lang="jp"><![CDATA[キャッシュに最適化]]></value>
+		<value xml:lang="zh-CN"><![CDATA[优化缓存]]></value>
+		<value xml:lang="tr"><![CDATA[Önbelleğe alma optimize]]></value>
+	</item>
+	<item name="about_cache_friendly">
+		<value xml:lang="ko"><![CDATA[Varnish 등의 캐싱 서버 사용시 성능 개선을 위해, 로그인하지 않은 사용자에게는 인증 세션을 부여하지 않습니다.<br>이 옵션을 선택할 경우 방문자 수 및 조회수 집계가 정확하지 않을 수 있습니다.]]></value>
+		<value xml:lang="en"><![CDATA[To improve performance when using a caching server such as Varnish, do not issue sessions to visitors until they log in.<br>Selecting this option may cause view counts and visitor counts to become inaccurate.]]></value>
+		<value xml:lang="jp"><![CDATA[Varnishなどのキャッシュサーバ使用時のパフォーマンスを向上させるために、ログインしていないユーザーには、認証セッションを付与しません。<br>このオプションを選択した場合、訪問者数とヒット集計が正確でない場合があります。]]></value>
+	</item>
 	<item name="sftp">
 		<value xml:lang="ko"><![CDATA[SFTP 사용]]></value>
 		<value xml:lang="en"><![CDATA[Use SFTP]]></value>

modules/admin/tpl/config_general.html

@@ -225,6 +225,15 @@
 				<label for="qmail_compatibility_n" class="x_inline"><input type="radio" name="qmail_compatibility" id="qmail_compatibility_n" value="N" checked="checked"|cond="$qmail_compatibility!='Y'" /> {$lang->cmd_no}</label>
 			</div>
 		</div>
+		<div class="x_control-group">
+			<label class="x_control-label">{$lang->cache_friendly}</label>
+			<div class="x_controls">
+				<label for="cache_friendly_y" class="x_inline"><input type="radio" name="cache_friendly" id="cache_friendly_y" value="Y" checked="checked"|cond="$cache_friendly=='Y'" /> {$lang->cmd_yes}</label>
+				<label for="cache_friendly_n" class="x_inline"><input type="radio" name="cache_friendly" id="cache_friendly_n" value="N" checked="checked"|cond="$cache_friendly!='Y'" /> {$lang->cmd_no}</label>
+				<br />
+				<p class="x_help-block">{$lang->about_cache_friendly}</p>
+			</div>
+		</div>
 		<div class="x_clearfix btnArea">
 			<div class="x_pull-right">
 				<button type="submit" class="x_btn x_btn-primary">{$lang->cmd_save}</button>