Add a python script to build, run and setup and tear down ip tables rules

This provides a single entry point and takes care of both setup and cleanup of the iptables rules. 

It's super convenient in that it will build local tweaks, and setup the iptables rules and strip them off when shutting down. 

It would be great to get feedback on this. I can polish it up and add documentation if you're interested in merging. 

I've also got a variant which enables the disk caching as it's very useful when using docker heavily for similar repeated tasks which is why I'm using local checkouts instead of the prebuilt image. I'll try to find a way to parameterize that too for submission back.