SPRINGFIELD — Illinois voters have the chance to sign up to send their ballots for November and spring elections by mail — forever.Elections officials are sending applications for permanent permission to vote by mail to each of the state’s 8 million registered voters.No one is obligated to sign up. But for as long as they stay at the same address, those who do will receive ballots they can complete at home and put in the mail for all future elections.“The availability of a permanent vote-by-mail …