improve NSDateFormatter performance, create it only once per thread.
improve NSDateFormatter performance, create it only once per thread.

lucasmedeirosleite/EasyMapping,ChronicStim/EasyMapping,keslcod/EasyMapping,maximgolunov/EasyMapping,maximgolunov/EasyMapping,PodsMakleso6/EasyMapping,lucasmedeirosleite/EasyMapping,ChronicStim/EasyMapping,jazzz13/EasyMapping,keslcod/EasyMapping,jazzz13/EasyMapping,PodsMakleso6/EasyMapping,ChronicStim/EasyMapping