* Add partial molar volume as a possible output

* And expose to python

* A fully encapsulated library wrapper with C++ interface

* Refactor types.hpp to hide the big headers in a macro conditional section

To check whether you have gotten to the critical point

* Split out reducing and mutants to their own headers

* Remove unused function

Refactor to avoid duplication

Add test and expose in Python

Based largely upon: https://pubs.acs.org/doi/abs/10.1021/acs.iecr.1c04703

TODO: apply polishing in another variable if constant composition polishing fails

So fast...

It's slow. Quite slow.

Couple of inlines are needed to avoid duplication of functions between compilation units

Fully works!