Bug 1088835 - have marionette-socket-host kick off runner-service 

if we add this to gaia's package.json/gaia-node-modules, then when someone runs 'make node_modules' for any reason, then it will install libzmq and update their python if necessary in the preinstall step. I was hoping to avoid doing that if it wasn't necessary to install. If you think it's fine, I'll add it to gaia tomorrow