WooCommerce Pre-Orders 2.1.0

Download WooCommerce Pre-Orders 2.1.0 from nulled fire. Allow customers to order products before they are available.
* Fix - When the Order is set to `completed` then the Pre-order should be in `completed` as well.
* Fix - Pre-Orders uses UTC instead of Local Time for cron.
* Fix - Rebuilt POT file.
* Fix - Cannot process payment of Completed Pre-Order if product is Out of Stock.
* Fix - Pre-Orders with a payment token present are displaying the wrong message.
* Fix - Variable product pre-orders not completing.
* Fix - Checking for zero cost order needs to account for floats.
* Tweak - Change pre-order complete interval to 1h instead of 5min.