Add exported profiles "legend"

[Carsopre]

Koswat version checks

• I have checked that the issue still exists on the latest version of the docs in master here.

Kind of issue

Documentation is missing

Location of the documentation

/docs/reference

• Probably is better to have a new chapter koswat_plots.
• Create subsections for base_profile and reinforced_profile.

Documentation problem

We do not have anywhere in the documentation a description on what each of the exported plots represent and how to interpret them.

Suggested fix for documentation

Describe in the documentation which line (and color) represents the base profile, which the reinforced one, and so on.
If required modified the code so that said colors are normalized.

So far:

• blue lines = base profile
• red lines = reinforced profile
• black lines = new surface layer