* 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()
* Tweak: Expanded API error message "No API resources exist." to provide instruction to both the customer and support to help resolve the issue.
* Fix: WooCommerce Subscriptions required version warning was displayed in cases where a very old version of WooCommerce Subscriptions was upgraded to the latest version.
