* Fix: Check if return value of $order->get_date_created() is null before calling $order->get_date_created()->date() to avoid fatal error in some edge cases.
* New: Added clear_database_cache() to clear cache when order status changes.
* Fix: Some clients may query the API Status function before the API Key activation is completed, causing an inactivate API Key status to be cached and returned, so the errant cache is cleared upon API Key activation if it exists.
* Fix: insert_setting_after() method called only when is_admin() == true caused fatal error in some cases.
* Fix: <a tag open in woocommerce-api-manager/includes/api/wc-am-api-requests.php.
* Fix: Changed improperly referenced get_row_data_by_activation_id() method to get_activation_resource_by_activation_id()
