So I am here, back in the overflow room at the Federal Palace of Justice downtown watching the Dallas City Hall federal corruption trial, and I see that we have come to one of the most fundamental and time-honored traditions of Dallas politics: that fine old institution called "walking-around money."Victor Vital, attorney for Sheila Hill, wife of former Dallas Mayor Pro Tem Don Hill, asked FBI agent Allen Wilson if he knew what "walking-around money" was. Wilson gave the wrong answer:"I have an