Suggestions for renamings of parameters

[hmgaudecker]

@janosg: Please disapprove where you see fit...

• [x] nemf -> n_mixture_components. Without recursing to the manual, it is impossible to find out what this is (note that all other things here https://skillmodels.readthedocs.io/en/latest/names_and_concepts.html#variables-related-to-dimensions do not have to be specified by the user)
• [x] kappa -> sigma_points_scale. Not described anywhere in docs, sigma_points module API docs do not show up so it is impossible to infer what is meant without looking up the CHS paper
• [x] probanch_function -> prob_anchoring_function. A bit more verbosity helps readability a lot.

Sort-of related: save_intermediate_optimization_results and save_path seem more useful as optional parameters to the fit() method rather than model-level constants. Same comment for start_params, start_values_per_quantity, maxiter, maxfun.

[janosg]

Probability anchoring was just dropped. I agree with the other renaming proposals.

Yes, save_intermediate_optimization_results, save_path, start_params, maxiter and maxfun should actually not be part of skillmodels and definitely not of the model specification but just be passed through to estimagic.maximize via the fit method.