Remove mention of obsolete Xcode versions
Remove mention of obsolete Xcode versions

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