Classes under "rulesets" have been moved to "rules", and split up into
futher subdirectories matching their library. As a result we can now
better separate the python bindings, so that things that belongs to the
simulation are separeted from things that belongs to the ai.
All IG code should use the interface of LocatedEntity when dealing
with any entity, rather than sometimes requiring Entity. Add virtual
functions to the interface where required, and modify all other interfaces
to stop them using Entity. This makes the code way cleaner, and much better
de-coupled.
