Set analogy-max-wt to 0.5
Renamed constants with +'s.
Define, use make-analogy-idxs-to-propn-idx.

make-analogy-idxs-to-propn-idx defined in nets,
and used in make-person.  Also added a field to Person to
contain the result of this function.
Added analogy-idxs-to-propn-idx to docstring for ->Person