MADISON, Wis. — While conservatives in Indiana and Arkansas were explaining last month why their new religious objections laws weren’t invitations to discriminate against gays, the leaders of Wisconsin’s capital city were busy protecting the rights of another group: atheists.In what is believed to be the first ordinance of its kind in the United States, Madison banned discrimination against the non-religious on April 1, giving them the same protections afforded to people based on their race, sexual …