Layer3 rigging

@rakitzis Please review.  This is a pair with the new changes to sample1 in the sample projects.  it will do a *very stupid* launch of the containers.

You can launch with:

pickett weather-client

This command builds (if necssary) and launches a weather server hooked to the weather client.  This is the sample code in sample1 using the libzmq library. Note that the graph of *running* nodes must form a DAG and you can only invoke a single node in the DAG (weather-client in the example abev).  See pickett.json for details about to config this up.

At the moment, it leaves lots of processes laying around that you have to kill.  You can see the leftovers with "docker ps" ... also, it's not clear it is smart about what to do if you hit control-c while the weather-client is running.