Celtic fans will have mixed emotions following their all-action Scottish Premiership clash against Aberdeen at Parkhead on Saturday. On one hand, Celtic’s draw to Aberdeen will feel like a defeat because they let a two-goal lead slip, but on the other, they are still unbeaten and going strong in all competitions. Take away Celtic’s horror Champions League defeat at Borussia Dortmund, for the most part, it has been plain sailing for the team this season. But Aberdeen made things uncomfortable for the champions, especially in the second half and the manner in which they did it was a talking poin…