LONDON (Reuters) - Investment bank JPMorgan said on Friday it now expected Britain and the European Union to reach a Brexit deal following an upbeat meeting on Thursday between Britain and Ireland's leaders."This changes everything - we now expect a deal," one of the bank's key Brexit watchers Malcolm Barr wrote in a note.While the exact details remain scant for the time being: "if our understanding of the situation is correct, a “solution” to the Irish border problem which could ultimately..