fixes #2353 update images with upload form (#2385)

Add a mode to update photos with the upload form. Modify the upload formats form, so that it will update the photo with the same file extension.

ws.php

@@ -262,7 +262,6 @@ function ws_addDefaultMethods( $arr )
       'pwg.images.formats.searchImage',
       'ws_images_formats_searchImage',
       array(
-        'category_id' => array('type'=>WS_TYPE_ID, 'default'=>null),
         'filename_list' => array(),
         ),
       'Search for image ids matching the provided filenames. <b>filename_list</b> must be a JSON encoded associative array of unique_id:filename.<br><br>The method returns a list of unique_id:image_id.',
@@ -500,6 +499,11 @@ function ws_addDefaultMethods( $arr )
           'type' => WS_TYPE_ID,
           'info' => 'id of the extended image (name/category/level are not used if format_of is provided)',
           ),
+        'update_mode' => array(
+          'default' => false,
+          'type' => WS_TYPE_BOOL,
+          'info' => 'true if the update mode is active',
+        ),
         'pwg_token' => array(),
         ),
       'Add an image.