claim_payments

One page of the claim payments waiting to be exported (Claims > Processing).

Code
Body: ``{search, page, page_size, sort_by, sort_order}``, all optional;
``sort_by`` is one of transaction_date (the default), claim_number, amount,
check_display or classification_name. Response: ``{page, page_size,
total_count, total_pages, payments}``. A page past the last one is an empty
list with the real total.