WP File Download - Joomunited 6.2.3

* Add : Pagination and load more options for file listing on admin
* Add : Possibility to add theme param to category shortcode
* Add : Possibility to order sub categories
* Add : Global settings for ordering direction for files and categories
* Fix : Import server files not work with uppercase file type
* Fix : Update date picker in the file search filter to avoid confusion
* Fix : Wrong pagination on frontend

* Fix : Error on JoomUnited file previewer, some servers prevent writing to PHP file
* Fix : Deleting the WP File Download plugin fails in some case
* Fix : WPML compatibility
* Fix : Wrong WP File Download pagination on cache

* Fix : Upload load file not working on frontend
* Fix : Wrong style on WP File Download Search engine