The artificial potential driver now builds correctly, and is even installed to /usr/local/lib/
Rename some cfg and world files; and removed the empty ones. The run_player script now creates a temporty .world file as well as a .cfg file, which are what the control scripts now parse.
Big effort to get the artificial potential code ported over to a plugin. No functionality is actually there; just trying to get the framework correct (which it isn't: problem with "unused" drivers).