merge r12725 from branch 2.3 to trunk

feature 2533 added: ability to deactivate uniqueness check on pwg.images.add


git-svn-id: http://piwigo.org/svn/trunk@12726 68402e56-0260-453c-a942-63ccdbb3a9ee

ws.php

@@ -241,6 +241,7 @@ function ws_addDefaultMethods( $arr )
         'maxValue' => $conf['available_permission_levels']
         ),
       'resize' => array('default' => false),
+      'check_uniqueness' => array('default' => true),
       ),
     'POST method only.
 <br><b>categories</b> is a string list "category_id[,rank];category_id[,rank]" The rank is optional and is equivalent to "auto" if not given.'