fixes #710 nn_device() failure on Windows
fixes #710 nn_device() failure on Windows

featherweight/ftw-kernel-nanomsg,snikulov/nanomsg,reqshark/nanomsg,reqshark/nanomsg,thisco-de/nanomsg,snikulov/nanomsg,featherweight/ftw-kernel-nanomsg,reqshark/nanomsg,thisco-de/nanomsg