ZeroMQ 3.x Output Plugin

Building this plugin:
Requires libzmq and libczmq. First, download the tarballs of both libzmq
and its supporting libczmq from http://download.zeromq.org. As of this
writing (04/23/2013), the most recent versions of libzmq and czmq are
3.2.2 and 1.3.2 respectively. Configure, build, and then install both libs.

Omzmq3 allows you to push data out of rsyslog from a zeromq socket.  The example
below binds a PUB socket to port 7171, and any message fitting the criteria will
be output to the zmq socket.

Example Rsyslog.conf snippet (NOTE: v6 format):
-------------------------------------------------------------------------------
if $msg then {
    action(type="omzmq3", sockType="PUB", action="BIND", 
           description="tcp://*:7172)
}
-------------------------------------------------------------------------------
