Merge remote-tracking branch 'upstr/master' into identity_fd
test case for zmq_getsockopt/ZMQ_IDENTITY_FD
Merge branch 'master' of https://github.com/zeromq/libzmq into identity_fd
Merge pull request #1031 from sdrsdr/identity_fd

test case for zmq_getsockopt/ZMQ_IDENTITY_FD