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

Added multipolar terms; doesn't compile on mac anymore

Another bugfix release is needed

Closes #34

Ready for Python!

And some tests

version 0.14.1

And get the parameters from the class

Closing in with the models

* A fully encapsulated library wrapper with C++ interface

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