Sub head: Running as 'a fighter who can win' and implement 'commonsense conservative reforms.'Scott Walker isn’t big on self-reflection. He spent much of Sunday on a this-is-your-life tour of southeastern Wisconsin with an ABC News production team and World News Tonight anchor David Muir. Late in the afternoon, he signed the biennial budget for the state of Wisconsin, a final item on the to-do list he compiled last winter as he began exploring a bid for the presidency. Today, Walker will formally announce his candidacy for the White House. It’s pretty heady stuff, but Walker, who grew up the son...