An old Charlotte County racetrack is back.  Three Palms Speedway in Punta Gorda hosted a stock-car-racing school Saturday.  WINK reports the property, which has seen better days, is getting n upgrade, with painting being done and new grandstands on the way.    Haase Enterprises is leasing the track from the Charlotte County Airport Authority and hopes to makes the business profitable again.   The new tenants say they have plans for weekly races, beginning after the 1st of the year. They say the property will host a variety of events to keep the venue profitable year round.