And get the parameters from the class

Closes #27

* Try to break up the C++ interface into smaller chunks

In order to make compilation less RAM intensive

* Inline the makers, also add the other sources

* Tidying up the splitting

Problem was mcx missing sqrt

This reverts commit 23e09bb7.

Recommended by static analysis in Xcode

(no implicit conversion of nlohmann::json to filesystem)

Updated the pybind11 interface

Makes it same as base model