It should be sufficient, now, to write a new version of the load_object()
function. That function won't be called unless we really want to load, so all
checking and parsing is taken care of before that.
Provide a simple API for loaded objects to interact with GNU make. I still
won't guarantee that this API won't change but it's much closer to something
that's supported and provides easy-to-use interfaces with a public header
file.
