Vettel keeps Ferrari ahead in testing

By Alan Baldwin BARCELONA (Reuters) - Sebastian Vettel kept Ferrari on top of the Formula One testing timesheets for the second day running on Tuesday even if champions Mercedes again led the mileage charts. The four-time champion's quickest lap of one minute 22.810 seconds around the Spanish Grand Prix circuit was 0.715 quicker than the next best Red Bull driven by Australian Daniel Ricciardo. The German's time was nearly two seconds faster than last year's Spanish Grand prix pole time set by N