Add 'udp-zmq-forwarder' script, imported from EventLogging

This patch adds a simple Python script that is designed to run as a daemon. It
reads line-oriented data from a UDP socket and forwards it to a ZeroMQ
publisher socket bound to the same port number, but TCP.

Change-Id: Ia7831add31e9655225afeebb1c2c7c499a22d919