Add more functionality for the default agent

* tweaks a few things to make the base-agent more modular
* adds endpoint.lua from rackspace-monitoring-agent
* changes gyp slightly to push down the pkg_name into lua-space
i load these here: https://github.com/virgo-agent-toolkit/virgo-base-agent/pull/98/files#diff-e406f7d6f732fcc7ab5906484d8dc575R156