v3 payments changes

In v3, there are a range of improvements and new features with payment operations.

v2	v3
Create a payment with `POST /v2/PayBills.json`. You can combine payments made to the same vendor, and also pay multiple vendors with the same request.	Creating a payment with `POST /v3/payments` enables 2 workflows. Pay a vendor for a created bill. Pay a vendor without creating a bill. In this case, an auto-generated `billId` is available in the response. The request and response field names have changed. Relevant fields are grouped under the `fundingAccount` and `processingOptions` objects. NOTE*: As of today, you cannot combine payments made to the same vendor or pay multiple vendors with the same request. These features will be available in the future. See Payments for more information.
Get payment details with `POST /v2/Crud/Read/SentPay.json`.	Get payment details with `GET /v3/payments/{paymentId}`. `paymentId` is now set as a path parameter. See Get payment details in the API reference for more information.
Get list of payments with `POST /v2/List/SentPay.json`.	Get list of payments with `GET /v3/payments`. Filtering and sorting values are now query parameters. For filtering, use the `filters=field:op:value` format . The operator values are now acronyms. For example, `=` is now `eq` and `>=` is now `gte`. For sorting, use the `sort=field:order` format. For example, sort by `createdTime` in the ascending order with `sort=createdTime:asc`. The response includes `nextPage` and `prevPage` values for you to navigate between the pages of results. See Search operations with lists for more information.
Cancel a payment with `POST /v2/CancelAPPayment.json`.	Cancel a payment with `POST /v3/payments/{paymentId}/cancel`. `paymentId` is now set as a path parameter. See Cancel a payment in the API reference for more information.
Void a payment with `POST /v2/VoidAPPayment.json`.	Void a payment with `POST /v3/payments/{paymentId}/void`. `paymentId` is now set as a path parameter. See Void a payment in the API reference for more information.