fixes #1419 add photos in a lounge as a temporary space

* at the end of the upload of after a maximum duration, move the photos from the lounge to their actual categories.
* do not invalidate user cache when photos are added in the lounge, thus avoiding to rebuild cache on every photo uploaded
* the lounge system activates itself only beyond 50k (by default) photo

install/db/160-database.php

@@ -0,0 +1,26 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | This file is part of Piwigo.                                          |
+// |                                                                       |
+// | For copyright and license information, please view the COPYING.txt    |
+// | file that was distributed with this source code.                      |
+// +-----------------------------------------------------------------------+
+
+if (!defined('PHPWG_ROOT_PATH'))
+{
+  die('Hacking attempt!');
+}
+
+$upgrade_description = 'add lounge table';
+
+pwg_query('
+CREATE TABLE `'.PREFIX_TABLE.'lounge` (
+  `image_id` mediumint(8) unsigned NOT NULL,
+  `category_id` smallint(5) unsigned NOT NULL,
+  PRIMARY KEY (`image_id`,`category_id`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8
+;');
+
+echo "\n".$upgrade_description."\n";
+
+?>

install/piwigo_structure-mysql.sql

@@ -260,6 +260,17 @@ CREATE TABLE `piwigo_languages` (
   PRIMARY KEY  (`id`)
 ) ENGINE=MyISAM;
 
+--
+-- Table structure for table `piwigo_lounge`
+--
+
+DROP TABLE IF EXISTS `piwigo_lounge`;
+CREATE TABLE `piwigo_lounge` (
+  `image_id` mediumint(8) unsigned NOT NULL DEFAULT '0',
+  `category_id` smallint(5) unsigned NOT NULL DEFAULT '0',
+  PRIMARY KEY (`image_id`,`category_id`)
+) ENGINE=MyISAM;
+
 --
 -- Table structure for table `piwigo_old_permalinks`
 --