v2.0: Adding a cancellation source value to subscription cancels.
v2.0: Improvement to card verifications with Stripe.
v2.0: Improvement to card verifications with PayPal Commerce Platform Advanced Card Payments.
v2.0: Improvement to whitespace handling in passwords.
v2.0: Fix to reCAPTCHA issues with Stripe.
v2.0: Fix to Square, Stripe, and PayPal Commerce Platform Advanced Card Payments with `updateinfo` checkouts.
v2.0: Adding a transaction `type` to the API response (to indicate whether the transaction was customer- or merchant-initiated).
v2.0: Restricting PayPal Commerce Platform Advanced Card Payment signup to only supported countries.
v2.0: Fix to ensure handling fees are added to flat-rate shipping on subscription renewals.
v2.0: Further improvements to PayPal Commerce Platform Advanced Card Payment error handling.
v2.0: Bugfix to prevent duplicate template transactions from being created on subscriptions paid via ACH.
API: Adding webhook documentation.