Prepare 1.3.9 Version release

protected/humhub/config/common.php

@@ -13,7 +13,7 @@ Yii::setAlias('@themes', '@webroot/themes');
 
 $config = [
     'name' => 'HumHub',
-    'version' => '1.3.9-pre',
+    'version' => '1.3.9',
     'basePath' => dirname(__DIR__) . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR,
     'bootstrap' => ['log', 'humhub\components\bootstrap\ModuleAutoLoader', 'queue', 'humhub\modules\ui\view\bootstrap\ThemeLoader'],
     'sourceLanguage' => 'en',
@@ -151,6 +151,7 @@ $config = [
             ],
         ],
         'mutex' => [
+
             'class' => 'yii\mutex\MysqlMutex'
         ],
     ],

protected/humhub/docs/CHANGELOG.md

@@ -1,8 +1,8 @@
 HumHub Change Log
 =================
 
-1.3.9  (Unreleased)
----------------------------
+1.3.9  (February 13, 2019)
+--------------------------
 
 - Fix: StreamSuppressedQuery with limit = 2 throws query not executed exception
 - Fix #3378: Update user in search index when group memberships changes