Delete --detailext, --detailcia, --saveext arguments

[pcubillos]

Should we remove these arguments? The way they are implemented is pretty much useless:

--detailext=filename:wn1,wn2,...
Save extinction at specified wavenumbers in filename.
--detailcia=filename:wn1,wn2,...
Save CIA extinction at specified wavenumbers in filename.
--saveext=
Save extinction array in this file which won’t need to be recomputed if only the radius scale (scale height) changes.

We should either remove them, or re-implement them into a useful tool, maybe save the whole arrays, rather than just at a few wns.

Saving the opacity for the atmospheric model would be actually useful (for the contribution plots).

[aj-foster]

Have you made a decision on which way to go?

[pcubillos]

Not yet, I think jasmina re-purposed these (or some of these) variables already. I'll take a look.