Replace missing headers as needed

Python part still needs to be fixed, almost there, compiles in clang again

The key point is to speed up compilation, and make it easier to develop, by using the packaged C++ interface more extensively

Added multipolar terms; doesn't compile on mac anymore

Updated the pybind11 interface

Finally done

So inconsistent in naming...

Not sure it helps...

Attach model specific methods at model construction

Dropped three more esoteric ones with good replacements

Closing in

Also a method to give more helpful error methods for EOS-specific methods

Everything seems pretty promising aside from the mutant, which requires additional thought. How can we store the mutant in AllowedModels

Compilation of user code is very fast now

Could also be helped by perfect branch prediction

The use of void* in the interface is not my favorite solution...

* A fully encapsulated library wrapper with C++ interface

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