public class CondenseExchange
This operation replaces groups of points connected (internally) by
e-exchange bonds with a single point. Bonds with other points (or groups of
points) are assumed to be f-exchange bonds (meaning that the group of points
has a single f-bond with the other point (or groups of points) and these
f-exchange bonds are replaced by a single f-bond.
Exchange group points will have a color that corresponds to the number of
exchange points, color1 + numPoints. color1 is assumed to be upper case;
Where possible, root points will be moved out of exchange groups. Where not
possible, the resulting color will be a lower-case version of
color1 + numPoints. color1 is assumed to be upper-case.