Add DateTime on administration introduction page (Useful to help user on the forum, ...)

Move history configuration in a other tab.
Use translation on picture hint (Kb).
Show hint oh the menu text (not only on counter)

git-svn-id: http://piwigo.org/svn/trunk@1884 68402e56-0260-453c-a942-63ccdbb3a9ee

include/functions.inc.php

@@ -840,7 +840,7 @@ function get_thumbnail_title($element_info)
   
   if (!empty($element_info['filesize']))
   {
-    $thumbnail_title .= ' : '.$element_info['filesize'].' KB';
+    $thumbnail_title .= ' : '.l10n_dec('%d Kb', '%d Kb', $element_info['filesize']);
   }
 
   return $thumbnail_title;