- allow acquirers to arbitrarily include info about the tx in the
processing page
- pending is now a valid state that could require customer action in the
payment processing page - don't blindly redirect to the return url of
another tx if a pending transaction is there
This latest change might mean that customers with many tx attempts might
have a sub-par experience as they may need to click manually on the
redirect url of a successful tx while before they were redirected
immediately.