Memo to KXVO anchor Calvert Collins: If you want to see how to attract younger viewers, drop the big wig and have someone bring you a tape of what they're doing at KMTV. Moving at a break-neck pace, "Action 3 News" debuted Wednesday night, running viewers through its 35-minute newscast at what seemed to be at least twice the speed of WOWT's "Ten at 10." In terms of sheer quantity of stories,