Add in a page for bug 822737 that shows a paginated list for a developer. A transaction is an entry in the Contributions table. This should be a page under the developer hub, behind a waffle switch. At the top put a form that allows the developer to filter by app, purchase/refund/chargeback, date and transaction id. This looks very similar to the already existing refund view, but that uses the Refund object. I don't think its worth conflating the two, but might be worth a bit of copy paste (see mkt/developers/views.py > refunds).