add middleware lock while dequeuing the stack
add middleware lock while dequeuing the stack

feryardiant/slim,akrabat/Slim,iinux/Slim,RealSelf/Slim,somjit2514/basic,juliangut/Slim,AndrewCarterUK/Slim,jaapverloop/Slim,JoeBengalen/Slim,samsonasik/Slim,mnapoli/Slim,Sam-Burns/Slim,iinux/Slim,iinux/Slim,opengeek/Slim,dopesong/Slim,designermonkey/Slim,slimphp/Slim,foxyantho/Slim