switch to cleaner swap and pop version
switch to cleaner swap and pop version

chenwenbin928/zmqpp,benjamg/zmqpp,zeromq/zmqpp,sunkin351/zmqpp,kernelim/zmqpp,kernelim/zmqpp,pin3da/zmqpp,datasift/zmqpp,xaqq/zmqpp,sunkin351/zmqpp,chenwenbin928/zmqpp,zeromq/zmqpp,xaqq/zmqpp,datasift/zmqpp,pin3da/zmqpp,benjamg/zmqpp