fixes #474 typo in msg.h comments
fixes #474 typo in msg.h comments

featherweight/ftw-kernel-nanomsg,reqshark/nanomsg,JackDunaway/featherweight-nanomsg,imp/nanomsg,yan97ao/nanomsg,JackDunaway/featherweight-nanomsg,zerotacg/nanomsg,zerotacg/nanomsg,thisco-de/nanomsg,snikulov/nanomsg,yan97ao/nanomsg,imp/nanomsg,wirebirdlabs/featherweight-nanomsg,snikulov/nanomsg,yan97ao/nanomsg,zerotacg/nanomsg,reqshark/nanomsg,thisco-de/nanomsg,imp/nanomsg,JackDunaway/featherweight-nanomsg,reqshark/nanomsg,wirebirdlabs/featherweight-nanomsg,featherweight/ftw-kernel-nanomsg,wirebirdlabs/featherweight-nanomsg