A federal appeals court Thursday revived a lawsuit challenging a policy limiting the number of books Cook County Jail inmates may possess.The 7th U.S. Circuit Court of Appeals did not rule on the merits of Gregory Koger’s contention that allowing inmates to possess only three books or magazines in their cells at a time violates the First Amendment.The court also did not rule on the merits of Koger’s allegation that guards seized more than 30 books from his cell and did not return them when he was released from …