- big update in thumbnail creation process : form is always shown with the

comprehensive list of pictures without thumbnails (no matter the
  directory) unless there are no thumbnail missing.

- thumbnail creation process : form parameters are saved between 2 thumbnail
  generations thanks to new process

- thumbnail creation process : can ask to create all missing thumbnails

- thumbnail creation process : default thumbnail width and height are
  configured in include/config.inc.php

- thumbnail creation process : errors due to no write access directories are
  catched


git-svn-id: http://piwigo.org/svn/trunk@695 68402e56-0260-453c-a942-63ccdbb3a9ee

include/config.inc.php

@@ -183,10 +183,17 @@ $conf['newcat_default_visible'] = 'true';
 $conf['newcat_default_status'] = 'public';
 
 // level_separator : character string used for separating a category level
-// to the sub level
+// to the sub level. Suggestions : ' / ', ' » ', ' → ', ' - ',
+// ' >'
 $conf['level_separator'] = ' / ';
 
 // paginate_pages_around : on paginate navigation bar, how many pages
 // display before and after the current page ?
 $conf['paginate_pages_around'] = 2;
+
+// tn_width : default width for thumbnails creation
+$conf['tn_width'] = 128;
+
+// tn_height : default height for thumbnails creation
+$conf['tn_height'] = 96;
 ?>