Add creation settings

[qubixes]

Fixes #258

This PR tries to add some more information about how the variable was created. It probably needs a little bit more testing.

[Samuwhale]

Looks good to me!

[vankesteren]

Looks good, the logic looks done! One question: does "creation settings" still cover the meaning? Would "fit parameters", fitting config, estimation settings be better?

[qubixes]

Looks good, the logic looks done! One question: does "creation settings" still cover the meaning? Would "fit parameters", fitting config, estimation settings be better?

I think those are okay as well. However, I think the point is that some distributions are not estimated / fitted, but simply defined. If you have a suggestion that also covers that use case, then that might be better than creation_settings.

[vankesteren]

After thinking more, I'd go for either:

• fit_method
• creation_method

I still think "fit" works, as the user is also "fitting", just not doing ML estimation

You can choose and merge!!

[qubixes]

After thinking more, I'd go for either:

* fit_method

* creation_method

I still think "fit" works, as the user is also "fitting", just not doing ML estimation

You can choose and merge!!

Okay, creation_method it is then!