Support static bind/connect url for the ZMQ PSA

[pnoltes]

Adds support for statically configured endpoint url / connects. Mainly to enable testing without the need for a discovery layer.

The configuration should be in the META/(pub|sub)/.properties

For static endpoints use (i.e.)
zmq.static.bind.url=ipc:///tmp/pubsub-pingtest
For static connects uses (i.e.):
zmq.static.connect.urls=ipc:///tmp/pubsub-pingtest