Updated README with new information about private methods
Updated README with new information about private methods

liuruxian/libextobjc,sandyway/libextobjc,WPDreamMelody/libextobjc,goodheart/libextobjc,sunfei/libextobjc,bboyesc/libextobjc,sanojnambiar/libextobjc,jiakai-lian/libextobjc,kolyuchiy/libextobjc,telly/libextobjc,KBvsMJ/libextobjc