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There were changes to the Teller API which meant the JSON parsing started to fail.

Mainly account_number_last_4_digits became account_number, and the responses no longer consist of some metadata and a data property (instead the latter is the whole response).

I fixed the parsing and made the unit tests pass. However I'm not comfortable at saying this isn't broken in some way since it's been over a year since I wrote code for it and my updates were naive. I wasn't very conscious of the semantics of the code I was altering.

• Unit tests have been written.
• Code has been refactored.

• Refactor towards v1.

• list counterparties gives access to a list of outgoing transactions grouped by their counterparty.
• Outgoing values are now positive since the word outgoing already describes a negative flow of money.

• list totals became list balances|outgoing|incoming again. It's easier to understand.
• show outgoing and show incoming now fetch the amounts of coming money out or into a bank account for the current month.

list balances became list totals and now supports [--amount-type=<at=incoming|outgoing|all>].