Give - Recurring Donations 2.9.0

* New: PayPal gateways are now updated to send the invoice prefix to the gateway so you can more easily differentiate between Give donation transactions and other transactions.
* Tweak: Adjusted how Stripe completes recurring donations using theie new API cancel at plan end functionality.
* Tweak: Removed usage of AJAX to speed up updating the recurring text when changing levels.
* Fix: Resolved an issue where the helpful text next to the final donation amount wasn't displaying properly on page load and changing gateways.
* Fix: Resolved amount formatting and position in recurring text when using a comma for your decimal and thousands separator.
* Fix: Corrected a sessions error occuring when donors would access their subscription history page.
* Fix: Important - if you are using PayPal Payments Pro (Payflow) please ensure in PayPal your IPN endpoint points to "mywebsite.com". This ensures that if you are using PayPal Standard alongside Payflow then the IPN will properly work for both endpoints and your renewals will properly be recorded in Give via IPN.
* Fix: PayPal Payments Pro (Payflow) will not incorrectly sync in non-completed renewals when manually syncing.
* Fix: PayPal Payments Pro (Payflow) will not sync "completed" subscriptions to "expired" when manually syncing.

* New: Donors now have the ability to adjust their subscription amounts.
* New: Added the Authorize.net eCheck recurring payment gateway.
* New: Added a "Subscriptions" section to the donor details screen.
* New: You can now customize Recurring email headings directly within the specific emails found at WP-admin > Settings > Emails.
* New: There is a new subscription notes area where the system and users can add notes similar to payments.
* New: Recurring now has it's own meta table for developers to store subscription related metadata.
* New: Provided a way for users to update the transaction ID of a subscription manually.
* New: When a subscription is created at Authorize.net the donor's email addresses is passed with the payment.
* Fix: Stripe 3D Secure payments are now supported for subscriptions.
* Fix: Ensure that two donations are not created whenever a user gives a recurring donation while using PayPal Pro.

* Important: You must be running Give Core 2.2.0+ in order to use this add-on update. Please update Give Core to the latest version prior to completing this update.
* Fix: There is an upgrade routine to correct renewal donations that are not properly associated with the correct payment level.
* Fix: If for some reason the parent transaction ID from the gateway isn't properly recorded you can now edit it manually.