WooCommerce API Manager 3.4.1

* New: Create, and allow access to, API Resources for Order status "processing" if WooCommerce > Settings > Products > Access Restriction > Grant access to downloadable products after payment is selected.
* New: Added method has_status_processing().
* Fix: Check if order object exists before proceeding in several methods to avoid errors when order does not exist.
* Fix: Clear data cache before deleting/removing order

* 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.