Britain and the European Union signed the deal on Wednesday and the British parliament will finalise its implementation, ending over four years of negotiation and safeguarding nearly $1 trillion of annual trade. The deal is tariff-free, but will involve a lot more paperwork for trade between the UK and EU. Both sides said it was a chance to begin a new chapter in a relationship forged as Europe rebuilt after World War Two, but which has often seen Britain as a reluctant participant in ever-t…