Log Message:
Import py27-txzmq-0.7.3 as wip/py-txZMQ.

txZMQ introduces support for general 0MQ sockets by class ZmqConnection that can
do basic event loop integration, sending-receiving messages in non-blocking
manner, scatter-gather for multipart messages.

txZMQ uses MQ APIs to get file descriptor that is used to signal pending
actions from MQ library IO thread running in separate thread. This is used in a
custom file descriptor reader, which is then added to the Twisted reactor