Allow constant species in condition table

[dweindl]

At the moment we do not allow constant species in the condition table. To have these concentrations condition-specific, the current way to go would be to turn those species into parameters. For the simulation this is fine.

However, this takes away the possibility of listing those species as reaction modifiers, which makes sense in terms of underlying biology and for model visualization. Furthermore, keeping those species as SBML species would allow for better annotation.

What was the motivation for not allowing constant species in the condition table?

[dweindl]

As agreed during today's discussion, this will be supported.

TODO:

• Update documentation
• Adapt linter code
• ?

[dweindl]

Done.