Present dialog on insufficient funds when sending coins
Clean up amount validation
Fix focus handling in send and request coins dialogs
Remember last exchange direction in send and request coins dialogs
Labs: Put BIP70 payment request on NFC tag and be prepared to read it
Labs: Put BIP70 payment request into QR-code and be prepared to read it
Labs: Use BIP70 PaymentMessage/PaymentACK messages in Bluetooth offline transaction protocol if payment was initiated by a PaymentRequest message
Open BIP70 payment requests from content-URIs, e.g. from e-mail attachments
Handle HTTP/HTTPS payment URLs
Show verified payee on 'send coins' dialog
Handle missing or invalid addresses in PaymentIntents
[WIP] Store outputs in PaymentIntent