[paymentrequest] Constructor should not include "total" in list of items (#68)

Right now the "total" cost of the transaction is reflected as an item in the items sequence of the details object.  This is an anti-pattern.  The total should be a separate item in that object (and, in fact, there should be no requirement for items - that is optional detail about the transaction). 

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/paymentrequest/issues/68