instead of using the property map interface.
A nice side-effect is that the wart of having to use property maps to loop over bonds or atom neighbors
is now gone.
This potentially breaks lots of client C++ code.
This "lookalike" implementation is much cruder than the real thing and does not really support
enabling and disabling logs, or associating them with files, but those components were not being
particularly used in the RDKit anyway.
