Boris Johnson, the Brexiteer who has promised to lead Britain out of the European Union with or without a deal by the end of October, will replace Theresa May as prime minister after winning the leadership of the Conservative Party on Tuesday... May will leave office on Wednesday after going to Buckingham Palace to see Queen Elizabeth, who will formally appoint Johnson. “We are going to get Brexit done on Oct. 31, and we are going to take advantage of all the opportunities it will bring in a new spirit of ‘can do’,” Johnson, 55, said after the result was...