It was a tiny sign of the times : the latest politician’s mistress to make headlines — Rielle Hunter, with whom John Edwards says he had an extramarital affair in 2006 — was no one’s nanny, secretary or intern. She was Edwards’s Web videographer. For $114,000, she turned out video installations (what people a few years ago called webisodes) in an online serial drama. “I have come to the personal conclusion that I actually want the country to see who I (...)