ATLANTA — Conservative groups accused Georgia Gov. Nathan Deal of turning his back on people of faith by vetoing a “religious freedom” bill and vowed Tuesday to keep up the fight for years to come. “This is only the beginning,” said Virginia Galloway, who represents the Faith and Freedom Coalition in Georgia. The bill enumerated actions that “people of faith” would not have to perform for others: Clergy could refuse to marry same-sex couples; church-affiliated religious groups could invoke faith as a reason to refuse to serve or hire someone.