xF1 Add-on sonnb - XenGallery - Video Upload 1.2.3

Compatible with the new XF HTML5 uploader.

- Fix watermark was not applied on animated thumbnails if using Imagick.
- Fix minor issue in he PHPVideoToolkit library which throws an exception while uploading video in PHP 5.3.0 which is a known issue of PHP 5.3.0.
- Fix minor issue in the PHPVideoToolkit library which throws an exception in the Server errors in some cases.
- Fix issue with animated thumbnail generation for very short videos.
- Fix issue when rebuilding contents.