Avoid using deprecated function zmq_recvmsg
Avoid using deprecated function zmq_recvmsg

The zmq_recvmsg() function has been replaced by zmq_msg_recv() since version 3.2.0, and has since been marked as deprecated.
See: https://raw.githubusercontent.com/zeromq/zeromq3-x/master/NEWS
Replace our uses of the old function (which was in monitor_t::monitor()) with the more modern function call. Support backwards compatibility with a #DEFINE macro for versions of zmq preceeding 3.2.0
michele-brambilla/ConfigurationService,zeromq/cppzmq,michele-brambilla/ConfigurationService,michele-brambilla/ConfigurationService,michele-brambilla/ConfigurationService,eburkitt/cppzmq,K0n63n/cppzmq,zeromq/cppzmq,michele-brambilla/ConfigurationService,cmcmurrough/cppzmq