They're back! No, we're not talking about uninvited guests or the evil television spirits from the move "Poltergeist." We're talking sales at J.C. Penney stores. Starting this week, the Plano-based retailer is bringing back some of the sales that it had banished to the woodshed last year. Forbes said the sales are exactly what CEO Ron Johnson said he wouldn't do when he initiated a new marketing and pricing strategy after taking the helm at Penney (NYSE: JCP). That strategy, which featured everyday…