WooCommerce Recommendation Engine 3.4.4

* New: Added a shortcode which can be used anywhere on the site to display Also Viewed and Also Purchased type recommendations. The recommendations are based on the users browsing history.
*Basic Syntax: [woocommerce_related_products_by_status label="Based on your viewing history" type="viewed"]
Type can be either "viewed" or "completed"

* Update: Add additional checking before starting the WC session.
* Update: Fix widget so that it uses a select box instead of a checkbox array for selecting which items to display.

* Fix: Correct issue with missing function in < WC 3.6